--- name: "xtrs" section: "1" platform: "linux" package: "xtrs" version: "4.9d-2.1" release: "Debian 13 (Trixie)" platforms: ["linux"] url: "https://new.carta.tech/xtrs" --- # xtrs(1) TRS-80 Model I/III/4/4P emulator for the X Window System ## Name **xtrs** - TRS-80 Model I/III/4/4P emulator for the X Window System ## Synopsis **xtrs** \[**-model** *m*\] \[**-diskdir** *d*\] \[**-debug**\] \[*other-options*\] ## Description **xtrs** is an emulator for a series of 8-bit microcomputers manufactured by Tandy/Radio Shack in the 1970s and 1980s. The program is built on top of a Zilog Z80 emulator, with added routines to support keyboard and video I/O through an X interface. The hardware emulation can operate as a TRS-80 Model I, Model III, Model 4, or Model 4P. **xtrs** supports 48kiB of RAM in Model I or Model III mode, and 128kiB in Model 4 or Model 4P mode. Floppy disks and hard disks are emulated using files to store the data; or under Linux only, real floppy drives can be used. A printer is emulated by sending its output to the standard output. A serial port is emulated using a Unix terminal device. Cassette I/O is emulated using files to store the cassette data; real cassettes can also be read or written (with luck), either directly through your sound card (on Linux and other systems with OSS-compatible sound drivers), or via *.wav* files. Game sound and music output are also supported if you have an OSS-compatible sound driver; sound output though the cassette port, through the Model 4 sound option, and through the optional Orchestra-85/90 music synthesizer card are all emulated. In Model I mode, the HRG1B graphics card is emulated. In Model III and 4/4P mode, you can select whether the Radio Shack graphics card or Micro Labs Grafyx Solution is emulated. There is also a mouse driver for Model 4/4P mode. Several common time-of-day clock cards are emulated on all models. The Alpha Products joystick is emulated using the keyboard's numeric keypad. Because **xtrs** emulates the hardware, all known TRS-80 Model I/III/4/4P operating systems should run on it, including all flavors of *TRSDOS*, *LDOS/LS-DOS*, *NEWDOS*, *DOSPLUS*, *MultiDOS*, and TRS-80 *CP/M*. However, the emulator also includes some extensions to the standard hardware, and the special drivers, utilities, and instructions needed for these are not provided for all operating systems. The Z80 emulator has a debugger called *zbx*. You can enter the debugger either by starting **xtrs** with the **-debug** flag or by pressing **F9** while **xtrs** is running. The debugger runs in the X terminal window that you started **xtrs** from. Once you are in the debugger, type **help** for more information. Special support in the emulator allows the program to block when waiting for information from the keyboard. This will work only for programs that wait for keyboard input using the standard Model I/III ROM call; the emulator decides whether to block the Z80 program when it tries to read from the keyboard memory by pattern-matching its stack. ### Keys The following keys on the host keyboard have special meanings to **xtrs**. **F11** toggles onscreen help on the keyboard mappings. **LeftArrow**, **Backspace**, or **Delete** is the TRS-80 left arrow key. **RightArrow** or **Tab** is the right arrow key. **UpArrow** is the up arrow key. **DownArrow** or **Linefeed** is the down arrow key. **Esc** or **Break** is the Break key. **Home** or **Clear** is the Clear key. **Control** is the Model 4 Ctrl key (address bit 7, data bit 2). **F12** is equivalent to the shifted down arrow key (used as a control key with some TRS-80 software). **F1**, **F2**, and **F3** are the Model 4/4P function keys (address bit 7, data bits 4, 5, and 6). **F1** is also the Model I Electric Pencil control key that some users added to their machines. **F4** is the Model 4 Caps Lock key (address bit 7, data bit 3). **F5**, **Compose**, or **ScrollLock** is equivalent to the @ key (so that @ can be used as a modifier key). **F6** is equivalent to the 0 key (so that a shifted 0 can be obtained). **F7** signals a floppy disk change (see **Emulated floppy disks**, below). **F8** exits the program. **F9** enters the *zbx* debugger. **F10** is the reset button. In Model III, 4, and 4P modes, the left and right **Shift** keys are distinct; in Model I mode, they are the same. The **PageUp** and **PageDown** keys always activate the positions that correspond to the Model III/4/4P left and right shift keys (address bit 7, data bits 0 and 1 respectively), even in Model I mode. The **End** key activates an unused position in the keyboard matrix (address bit 7, data bit 7). The keys **\[**, **\\**, **\]**, **^**, and **\_** also activate unused positions in the keyboard matrix (address bit 3, data bits 3–7), as do the ASCII-shifted counterparts of the first four (**{**, **\|**, **}**, and **~**); see above regarding **Delete**. With many TRS-80 keyboard drivers, these keys map to the corresponding ASCII characters; with others, they do nothing. In some cases you may find the shift state reversed from what you expect; if, for instance, you press **\[** but “{” is displayed instead, see **-shiftbracket** and **-noshiftbracket** in **Options**, below, to correct the problem. The **Insert** key maps to the same position as underscore (address bit 3, data bit 7), so that this key can be used both with and without shift pressed; with many TRS-80 keyboard drivers one of these maps to ASCII code 0x7f (DEL). On a German keyboard, the **¨** and **ß** keys should activate the corresponding characters used in the GENIE, a German Model I clone. This feature is most useful together with the **-charset genie** command-line option. Pressing a key on a PC-style keyboard's numeric keypad with **NumLock** disengaged emulates the Alpha Products joystick. Keys 2, 4, 6, and 8 (**KP\_Down**, **KP\_Left**, **KP\_Right**, and **KP\_Up**) are the main directions; keys 1, 3, 7, and 9 (**KP\_End**, **KP\_Page\_Down**, **KP\_Home**, **KP\_Page\_Up**) work as diagonal directions by activating two main directions at once; and key 0 (**KP\_Insert**) or 5 (**KP\_Begin**) is the fire button. Note that your X server may default to sending digits for the keys on the numeric pad even if **NumLock** is not active. If you have this problem, you can use [**xev**(1)](/xev/1.md) to determine the names of the X keysyms generated by your keystroke events. You may need to check or update your XKB configuration. Alternatively, you can use [**xmodmap**(1)](/xmodmap/1.md) to remap your numeric pad. ### Emulated cassette To control the emulated cassette, a file called *.cassette.ctl* in the current working directory keeps track of what file is currently loaded as the cassette tape and the current position within that file. The [**cassette**(1)](/cassette/1.md) shell script provides a way to manipulate this file. You may use this script to load and position cassette tape files. The operation works very much like an actual tape recorder. The **cassette** man page has more information about the shell script and the cassette file formats that are supported. ### Printer For printer support, any text sent to the TRS-80's printer (using LPRINT or LLIST, for example) is sent to the standard output. ### Emulated floppy disks In Model I mode, **xtrs** emulates a Radio Shack Expansion Interface with the Percom Doubler or Radio Shack Doubler installed. The Doubler provides double-density disk access by allowing either the stock WD1771 FDC chip or a WD1791 chip to be selected under program control. At powerup the 1771 is selected, so operating systems with no Doubler driver see a stock system. By default, the emulator pretends to be both a Percom and Radio Shack Doubler at the same time—it responds to the special commands of both—so a driver for either should work. Under *LDOS* use the command *FDUBL* (on newer versions of *LDOS*), or *PDUBL* or *RDUBL* (on older versions) to install the driver. Software that tries to detect which doubler you have (such as *Super Utility*) may be confused by the emulation of both at once, so you can choose to emulate only one with a command-line option; see **Options** below. In Model III, 4, or 4P mode, **xtrs** emulates the stock floppy controller, which uses a WD1793 chip (software-compatible with the WD1791) to provide both single and double density. Four 5¼-inch floppy drives are emulated, with storage in files named *disk*M*-*U, where *M* is the TRS-80 model (**1**, **3**, **4**, or **4p**) and *U* is the drive unit number (**0**, **1**, **2**, or **3**). If a file of the required name is not found, a drive with no disk in it is emulated (but see below). If the user does not have write permission for a floppy file, and/or the file has an internal write protect flag set, a write-protect tab is emulated. Use the [**mkdisk**(1)](/mkdisk/1.md) program to turn the write protect flag on or off. To change floppies in an emulated drive, rename the existing file for the drive (if any), rename the new floppy file to the proper name, and press **F7** (see **Keys,** above). If you try to boot an emulated Model I, III, or 4 with no file named *disk*M*-0* (that is, no disk in drive 0), **xtrs** emulates having no floppy disk controller. The behavior of a real machine with a disk controller in this case didn't seem useful to emulate faithfully: a real Model I hangs with a screen full of garbage; a real Model III or 4 goes into a retry loop printing "Diskette?" on the screen and rechecking whether you've inserted one. A real Model 4P always has a floppy controller, however, so **xtrs** always emulates one. Due to a limitation of the original Model I hardware, drive :3 cannot be double-sided in Model I mode. In the original Model I, you could not have a drive :3 at all if any drive in the system was double-sided, but the emulator is able to be more forgiving. Emulated floppy image files can be of any of three types: JV1, compatible with Jeff Vavasour's popular freeware Model I emulator for *MS-DOS*; JV3, a compatible extension of a format first used in Vavasour's commercial Model III/4 emulator; or DMK, compatible with David Keil's Model 4 emulator. All three types work in **xtrs** regardless of what model it is emulating. A heuristic is used to decide which type of image is in a drive, as none of the types has a magic number or signature. JV1 supports only single-sided, single-density diskettes, with directory on track 17. Sectors must be 256 bytes long. Use **FORMAT (DIR=17)** if you want to format JV1 disks with more (or less) than 35 tracks under *LDOS*. JV3 is much more flexible, though it still does not support everything the real controllers could do. It is probably best to use JV3 for all the disk images you create, since it is the most widely implemented by other emulators, unless you have a special reason to use one of the others. A JV3 disk can be formatted with 128, 256, 512, or 1024-byte sectors, 1 or 2 sides, single or double density, with either an 0xFB (normal) or 0xF8 (deleted) data address mark on any sector. On single-density JV3 disks, the nonstandard data address marks 0xFA and 0xF9 are also available. You cannot format a sector with an incorrect track number or head number. You *can* format a sector with an intentional CRC error in the data field. **xtrs** supports at most 5802 total sectors on a JV3 image. The original Vavasour JV3 format supported only 256-byte sectors, and had a limit of 2901 total sectors. If you use sector sizes other than 256 bytes or format more than 2901 sectors on a disk image, emulators other than **xtrs** may be unable to read it. Note that an 80 track, double-sided, double-density (18 sector) 5¼-inch floppy will fit within the original 2901 sector limit; the extension to 5802 is primarily for emulation of 8-inch drives (discussed below). The DMK format is the most flexible. It supports essentially everything that the original hardware could do, including all “protected” disk formats. However, a few protected disks still may not work with **xtrs** due to limitations in **xtrs**'s floppy disk controller emulation rather than limitations of the DMK format; see **Bugs and limitations**, below. The program [**mkdisk**(1)](/mkdisk/1.md) makes a blank emulated floppy or “bulk erases” an existing one. By default, **mkdisk** makes a JV3 floppy, but with the **-1** flag it makes a JV1 floppy, or with the **-k** flag a DMK floppy. See the **mkdisk** man page for more information. Early Model I operating systems used an 0xFA data address mark (DAM) for the directory on single-density disks, while later ones wrote 0xF8 but would accept either upon reading. The change was needed because 0xFA is a nonstandard DAM that is fully supported only by the WD1771 floppy disk controller used in the Model I; the controllers in the Model III and 4 cannot distinguish between 0xFA and 0xFB (which is used for non-directory sectors) upon reading, and cannot write 0xFA. To deal nicely with this problem, **xtrs** implements the following kludge. On writing in single density, an 0xF8 data address mark is recorded as 0xFA. On reading with an emulated WD1771 (available in Model I mode only), 0xFA is returned as 0xFA; on reading with a WD179*x*, 0xFA is returned as 0xF8. This trick makes the different operating systems perfectly compatible with each other, which is better than on a real Model I! You can use the **-truedam** flag to turn off this kludge if you need to; in that case the original hardware is emulated exactly. TRS-80 programs that attempt to measure the rotational speed of their floppy disk drives using timing loops will get the answers they expect, even when **xtrs** does not emulate instructions at the same speed as the original machines. This works because **xtrs** keeps a virtual clock (technically, a T-state counter), which measures how much time it should have taken to execute the instruction stream on a real machine, and it ties the emulation of floppy disk index holes to this clock, not to real time. ### Emulated 8-inch floppy disks In addition to the four standard 5¼-inch drives, **xtrs** also emulates four 8-inch floppy drives. There is no widely-accepted standard hardware interface for 8-inch floppies on the TRS-80, so **xtrs** emulates a pseudo-hardware interface of its own and provides an *LDOS*/*LS-DOS* driver for it. Storage for the emulated 8-inch disks is in files named *disk*M*-*U, where *M* is the TRS-80 model (**1**, **3**, **4**, or **4p**) and *U* is the drive unit number (**4**, **5**, **6**, or **7**). The only difference between 5¼-inch and 8-inch emulated drives is that the emulator allows you to format more bytes per track in the latter. A new JV3 floppy can be formatted as either 5¼-inch or 8-inch depending on whether you initially put it into a 5¼-inch or 8-inch emulated drive. A new DMK floppy, however, must be created with the **-8** flag to **mkdisk** in order to be large enough for use in an 8-inch emulated drive. JV1 floppies cannot be used in 8-inch drives. Be careful not to put an emulated floppy into a 5¼-inch emulated drive after it has been formatted in an 8-inch emulated drive or vice versa; the results are likely to be confusing. Consider using different file extensions for the two types; say, *.dsk* for 5¼-inch and *.8in* for 8-inch. To use the emulated 8-inch drives, you'll need a driver. Under *LDOS* or *LS-DOS*, use the program *XTRS8/DCT* supplied on the emulated floppy *utility.dsk*. This driver is a very simple wrapper around the native *LDOS*/*LS-DOS* floppy driver. Here are detailed instructions. First, make sure an appropriate version of *LDOS* is in emulated floppy drive 0, and the supplied file *utility.dsk* is in another emulated floppy drive. Boot *LDOS*. If you are using Model I *LDOS*, be sure *FDUBL* is running. Second, type the following commands. Here *d* is the *LDOS* drive number you want to use for the 8-inch drive and *u* is the unit number you chose when naming the file. Most likely you will choose *d* and *u* to be equal to reduce confusion. ``` SYSTEM (DRIVE= d d d ,DRIVER="XTRS8",ENABLE) Enter unit number ([4]-7): u u ``` ***You can repeat these steps with different values of*** *d* ***and*** *u* ***to have more than one 8-inch drive.*** ***You might want to repeat four times using*** **4**, **5**, **6**, ***and*** **7**, ***or you might want to save some drive numbers for hard drives (see below).*** ***Finally, it's a good idea to give the*** *SYSTEM (SYSGEN)* ***command (Model I/III) or*** *SYSGEN* ***command (Model 4/4P).*** ***This command saves the*** *SYSTEM* ***settings, so the 8-inch drives will be available again the next time you reboot*** ***or restart the emulator.*** ***If you need to access an 8-inch drive after booting from a disk that hasn't been*** *SYSGEN*ed, ***simply use the same*** *SYSTEM* ***command again.*** ***In case you want to write your own driver for another TRS-80 operating system,*** ***here are details on the emulated pseudo-hardware.*** ***The 8-inch drives are accessed through the normal floppy disk controller,*** ***exactly like*** ***5******¼******-inch drives.*** ***The four*** ***5******¼******-inch drives have hardware select codes*** ***1, 2, 4, and 8, corresponding respectively to files*** *disk*M*-0,* *-1*, *-2*, ***and*** *-3*. ***The four 8-inch drives have hardware select codes 3, 5, 6, and 7, corresponding*** ***respectively to files*** *disk*M*-4,* *-5*, *-6*, ***and*** *-7*. ***(See also the*** **-sizemap** ***option below, however.)*** ### Real floppy disks ***Under Linux only, any*** *disk*M*-*U ***file can be a symbolic link to a real floppy disk drive, typically*** */dev/fd0* ***or*** */dev/fd1*. ***Most machines with “legacy” (ISA bus) floppy drive support should be able*** ***to read and write TRS-80-compatible floppies in this way.*** ***Many floppy controllers cannot handle single density, however, and some may have*** ***problems even with double-density disks written on a real TRS-80, especially*** ***disks formatted by older TRS-80 operating systems.*** ***Use the*** **-doublestep** ***flag if you need to read 35-track or 40-track media in an 80-track drive.*** ***If you need to write 35-track or 40-track media in an 80-track drive, bulk-erase*** ***the media first and format it in the 80-track drive.*** ***Don't write to a disk in an 80-track drive if it has ever been written to in a*** ***40-track drive.*** ***The narrower head used in an 80-track drive cannot erase the full track width*** ***written by the head in a 40-track drive.*** ***If you link one of the*** ***5******¼******-inch floppy files*** (*disk*M*-0* ***through*** *disk*M*-3*) ***to a real floppy drive, TRS-80 programs will see it as a*** ***5******¼******-inch drive, but the actual drive can be either*** ***3******½******-inch or*** ***5******¼******-inch.*** ***The drive will be operated in double density (or single density), not high*** ***density, so be sure to use the appropriate media.*** ***If you link one of the 8-inch floppy files*** (*disk*M*-4* ***through*** *disk*M*-7*) ***to a real floppy drive, TRS-80 programs will see it as an 8-inch drive.*** ***Again, you need to use the*** *XTRS8/DCT* ***driver described above to enable*** *LDOS*/*LS-DOS* ***to access an 8-inch drive.*** ***The real drive can be either*** ***3******½******-inch,*** ***5******¼******-inch,*** ***or 8-inch.*** ***A*** ***3******½******-inch or*** ***5******¼******-inch drive will be operated in high-density mode, using MFM recording if the*** ***TRS-80 is trying to do double density, or FM recording if the TRS-80 is trying*** ***to do single density.*** ***In this mode, these drives can hold as much data as a standard 8-inch drive.*** ***In fact, a*** ***5******¼******-inch HD drive holds exactly the same number of bits per track as an 8-inch*** ***drive; a*** ***3******½******-inch HD drive can hold 20% more, but we waste that space when using one to*** ***emulate an 8-inch drive.*** ***In both cases we also waste the top three tracks, since an 8-inch drive has only*** ***77 tracks, not 80.*** ***The nonstandard 0xFA and 0xF9 data address marks available in single density on*** ***a real Model I with the WD1771 controller also need special handling.*** ***A ISA-bus floppy disk controller can neither read nor write sectors with such*** ***DAMs at all.*** ***This raises three issues.*** - 1\. ***It will be impossible for you to read some Model I disks on your machine even if*** ***it otherwise supports single density.*** ***In particular, Model I*** *TRSDOS* ***2.3 directory tracks will be unreadable.*** - 2\. ***On writing in*** ***single density,*** **xtrs** ***silently records a 0xF9 or 0xFA DAM as 0xF8.*** - 3\. ***On reading in single density with an emulated WD1771 (Model I mode only), 0xF8*** ***is returned as 0xFA.*** ***If you need more accurate behavior, the*** **-truedam** ***flag will turn on error messages on attempts to write 0xF9 or 0xFA DAMs and will*** ***turn off translation of 0xF8 to 0xFA on reading.*** *Hint:* ***Be sure to set the drive type correctly in your machine's firmware.*** ***Linux and*** **xtrs** ***rely on this information to know how fast your drives are spinning and hence*** ***what data rate to use when reading and writing.*** ***All*** ***3******½******-inch drives spin at 300 rpm.*** ***Newer*** ***5******¼******-inch high-density capable drives (“1.2MB” drives) normally always spin at*** ***360 rpm.*** ***(Some can be jumpered to slow down to 300 rpm when in double-density mode, but*** ***you should not do that when connecting one to a floppy disk controller designed*** ***for ISA-bus machines.*** ***Older*** ***5******¼******-inch drives that cannot do high density (“180kB”, “360kB”, or*** ***“720kB”*** ***5******¼******-inch drives) always spin at 300 rpm.*** ***All 8-inch drives spin at 360 rpm.*** ***If you plug an 8-inch drive into an ISA-bus floppy disk controller—this*** ***requires a 50-pin to 34-pin adaptor cable—tell your firmware that it is a*** ***5******¼******-inch 1.2MiB drive.*** ### Emulated hard disks **xtrs** ***can emulate a hard disk in a file in one of two ways: it*** ***can use a special,*** **xtrs**-specific *LDOS* ***driver called*** *XTRSHARD/DCT*, ***or it can emulate the Radio Shack hard drive controller (based on the Western*** ***Digital WD1010) and use the native drivers for the original hardware.*** **Using** ***XTRSHARD/DCT*** ***XTRSHARD/DCT*** ***The*** *XTRSHARD/DCT* ***driver has been tested and works under both*** *LDOS* ***5.3.1 for Model I or III and*** *TRSDOS*/*LS-DOS* ***6.3.1 for Model 4/4P.*** ***It may or may not work under earlier*** *LDOS* ***versions.*** ***It definitely will not work under other TRS-80 operating systems or with*** ***emulators other than*** **xtrs**. ***The hard disk format was designed by Matthew Reed for his Model I/III and Model*** ***4 emulators;*** **xtrs** ***duplicates the format so that users can exchange hard drive images across the*** ***emulators.*** - ***To use*** *XTRSHARD/DCT*, ***first run the*** [**mkdisk**(1)](/mkdisk/1.md) ***program to create a blank hard drive*** (*.hdv*) ***file.*** ***A typical usage*** ***would be*** **mkdisk -h myhd.hdv**. ***See the*** **mkdisk** ***man page for other options.*** - ***Second, link the file to an appropriate name.*** *XTRSHARD/DCT* ***supports up*** ***to eight hard drives, with names of the form*** *hard*M*-*U, ***where*** *M* ***is the TRS-80 model*** (**1**, **3**, ***or*** **4**; ***in this case the Model 4P also uses*** *M*=4) ***and*** *U* ***is a unit number in the range 0–7.*** ***It looks for these files in the same directory as the floppy disk files*** *disk*M*-*U. - ***Third, make sure an appropriate version of*** *LDOS* ***is in emulated floppy drive 0, and the supplied file*** *utility.dsk* ***is in another emulated floppy drive.*** ***Boot*** *LDOS*. ***If you are using Model I*** *LDOS* ***5.3.1, patch a bug in the*** *FORMAT* ***command by typing*** **PATCH FORMAT/CMD.UTILITY M1FORMAT/FIX**. ***You need to apply this patch only once.*** ***It must not be applied to Model III or Model 4/4P*** *LDOS*. - ***Fourth, type the following commands.*** ***Here*** *d* ***is the*** *LDOS* ***drive number you want to use for the hard drive (a typical choice would be*** **4**) ***and*** *u* ***is the unit number you chose when naming the file (most likely*** **0**). ``` SYSTEM (DRIVE= d d ,DRIVER="XTRSHARD",ENABLE) Enter unit number ([0]-7): u u FORMAT d d (DIR=1) ``` ***Answer the questions asked by*** *FORMAT* ***as you prefer.*** ***The*** **DIR=1** ***parameter to*** *FORMAT* ***is optional; it causes the hard drive's directory to be on track 1, making the*** ***initial size of the image smaller.*** ***You can repeat these steps with different values of*** *d* ***and*** *u* ***to have more than one hard drive.*** - ***Finally, it's a good idea to give the*** *SYSTEM (SYSGEN)* ***command (Model I/III) or*** *SYSGEN* ***command (Model 4/4P).*** ***This command saves the*** *SYSTEM* ***settings, so the drive will be available again the next time you reboot or*** ***restart the emulator.*** - ***If you need to access the hard disk file after booting from a floppy that hasn't*** ***been*** *SYSGEN*ed, ***simply use the same*** *SYSTEM* ***command(s) again, but don't*** *FORMAT*. ***You can freely use a different drive number or (if you renamed the hard disk*** ***file) a different unit number.*** - ***The*** **F7** ***key currently doesn't allow*** *XTRSHARD/DCT* ***disk changes to be recognized, but you can change to a different hard disk file*** ***for the same unit by renaming files as needed and rebooting*** *LDOS*. - *Technical note:* *XTRSHARD/DCT* ***is a small Z80 program that implements all the required functions of an*** *LDOS* ***disk driver.*** ***Instead of talking to a real (or emulated) hard disk controller, however, it*** ***uses special support in*** **xtrs** ***that allows Z80 programs to open, close, read, and write Unix files directly.*** ***This support is described further in*** **Data import and export**, ***below.*** **Using native hard disk drivers** ***Beginning in version 4.1,*** **xtrs** ***also emulates the Radio Shack hard disk controller (based on the Western Digital*** ***WD1010) and will work with the native drivers for this hardware.*** ***This emulation uses the same hard drive*** (*.hdv*) ***file format that*** *XTRSHARD/DCT* ***does.*** ***With*** *LDOS*/*LS-DOS*, ***the*** *RSHARD*x*/DCT* ***and*** *TRSHD/DCT* ***drivers are known to work.*** ***With Montezuma*** *CP/M* ***2.2, the optional Montezuma hard disk drivers are known to work.*** ***The hard disk drivers for*** *NEWDOS/80* ***and for Radio Shack*** *CP/M* ***3.0 should work, but they have not yet been tested at this writing.*** ***Any bugs should be reported.*** - ***To get started, run the*** [**mkdisk**(1)](/mkdisk/1.md) ***program to create a blank hard drive*** (*.hdv*) ***file.*** ***A typical usage*** ***would be*** **mkdisk -h myhd.hdv**. ***See the*** **mkdisk** ***man page for other options.*** - ***Second, link the file to an appropriate name.*** ***The WD1010 emulation supports up to four hard drives, with names of the form*** *hard*M*-*U, ***where*** *M* ***is the TRS-80 model*** (**1**, **3**, **4**, ***or*** **4p**) ***and*** *U* ***is a unit number in the range 0–3.*** ***It looks for these files in the same directory as the floppy disk files*** *disk*M*-*U. ***If no such files are present,*** **xtrs** ***disables the WD1010 emulation.*** - ***Note that if hard drive unit 0 is present on a Model 4P (file*** *hard4p-0*), ***the Radio Shack boot ROM will always try to boot from it, even if the operating*** ***system does not support booting from a hard drive.*** ***If you have this problem, either hold down*** **F2** ***while booting to force the ROM to boot from floppy, or simply avoid using unit*** ***number 0.*** ***Stock*** *TRSDOS*/*LS-DOS* ***6 systems do not support booting from a hard drive; M.A.D. Software's*** *HBUILD6* ***add-on to*** *LS-DOS* ***for hard drive booting should work, but is untested.*** ***Montezuma*** *CP/M* ***2.2 does boot from the emulated hard drive.*** - ***Finally, obtain the correct driver for the operating system you will be using,*** ***read its documentation, configure the driver, and format the drive.*** ***Detailed instructions are beyond the scope of this manual page.*** ### Data import and export ***Several Z80 programs for data import and export from various TRS-80 operating*** ***systems are included with*** **xtrs** ***on two emulated floppy images.*** ***These programs use special support in the emulator to read and write external*** ***Unix files, discussed further at the end of this section.*** ***The emulated floppy*** *utility.dsk* ***contains some programs for transferring data between the emulator and ordinary*** ***Unix files.*** *IMPORT/CMD*, *EXPORT/CMD*, ***and*** *SETTIME/CMD* ***run on*** ***the emulator under Model I/III*** *TRSDOS*, ***Model I/III*** *LDOS*, ***Model I/III*** *NEWDOS/80*, ***and Model 4/4P*** *TRSDOS*/*LS-DOS* ***6; they may also work under other TRS-80 operating systems.*** ***Model III*** *TRSDOS* ***users will have to*** ***use*** *TRSDOS*'s *CONVERT* ***command to read*** *utility.dsk*. *IMPORT/CMD* ***imports a Unix file and writes it to an emulated disk.*** - ***Usage:*** **IMPORT** \[**-lne**\] *unixfile* \[*trsfile*\] - ***The*** **-n** ***flag converts*** ***Unix newlines (\\n) to TRS-80 newlines (\\r).*** ***The*** **-l** ***flag converts the Unix filename to lowercase, to compensate for TRS-80*** ***operating systems such as*** *NEWDOS/80* ***that convert all command-line arguments to uppercase.*** ***When using the*** **-l** ***flag, you can put a*** **\[** ***or up-arrow in front of a character to keep it in uppercase.*** ***Give the*** **-e** ***flag if your TRS-80 operating system uses the*** *NEWDOS/80* ***convention for representing the ending record number in an open file control*** ***block.*** ***This should be detected automatically for*** *NEWDOS/80* ***itself and for*** *TRSDOS* ***1.3, but you'll need to give the flag for*** *DOSPLUS* ***and possibly*** ***other*** non-*LDOS* ***operating systems.*** ***If you need the flag but don't give it (or vice versa), imported files will come*** ***out the wrong length.*** ***If the destination file is omitted,*** *IMPORT* ***uses the last component of the Unix pathname, but with any “.” changed to*** ***“/” to match TRS-80 DOS file extension syntax.*** *EXPORT/CMD* ***reads a file from an emulated disk and exports it to a Unix file.*** - ***Usage:*** **EXPORT** \[**-lne**\] *trsfile* \[*unixfile*\] - ***The*** **-n** ***flag converts TRS-80 newlines (\\r) to Unix newlines (\\n).*** ***The*** **-l** ***flag converts the Unix filename to lowercase.*** ***When using the*** **-l** ***flag, you can put a*** **\[** ***or up-arrow in front of a character to keep it in uppercase.*** ***Give the*** **-e** ***flag if your TRS-80 operating system uses the*** *NEWDOS/80* ***convention for representing the ending record number in an open file control*** ***block.*** ***This should be detected automatically for*** *NEWDOS/80* ***itself and for*** *TRSDOS* ***1.3, but you'll need to give the flag for*** *DOSPLUS* ***and possibly*** ***other*** non-*LDOS* ***operating systems.*** ***If you need the flag but don't give it (or vice versa), imported files will come*** ***out the wrong length.*** ***If the destination file is omitted,*** *EXPORT* ***uses the TRS-80 filename, but with any “/” changed to “.” to match*** ***Unix file extension syntax.*** - *Note:* ***The export of files from*** **xtrs** ***may be prohibited by the*** **-emtsafe** ***flag; see*** **Options**, ***below.*** *SETTIME/CMD* ***reads the date and time from Unix and sets the TRS-80 DOS's date and time*** ***accordingly.*** ***The next several programs were written in Misosys C and exist in two versions on*** *utility.dsk*. ***The one whose name ends in “6” runs on Model 4*** *TRSDOS*/*LS-DOS* 6.*x*; ***the other runs on*** *LDOS* 5.*x* ***and most other Model I/III operating systems.*** *CD/CMD* ***(or*** *CD6/CMD*) ***changes*** **xtrs**'s ***current working directory under Unix.*** - ***Usage:*** **CD** \[**-l**\] *unixdir* - ***The*** **-l** ***flag converts the Unix directory name to lowercase.*** ***When using the*** **-l** ***flag, you can put a*** **\[** ***or up-arrow in front of a character to keep it in uppercase.*** ***Running*** *CD/CMD* ***will change the interpretation of any relative pathnames given to*** *IMPORT* ***or*** *EXPORT*. ***It will also change the interpretation of disk names at the next disk change,*** ***unless you specified an absolute pathname for*** **xtrs**'s **-diskdir** ***parameter.*** - *Note:* ***The change of*** **xtrs**'s ***current working directory may be prohibited by the*** **-emtsafe** ***flag; see*** **Options**, ***below.*** *PWD/CMD* ***(or*** *PWD6/CMD*) ***prints*** **xtrs**'s ***current working directory under Unix.*** *UNIX/CMD* ***(or*** *UNIX6/CMD*) ***runs a Unix shell command.*** - ***Usage:*** **UNIX** \[**-l**\] *unix-command-line* - ***The*** **-l** ***flag converts the Unix command line to lowercase.*** ***When using the*** **-l** ***flag, you can put a*** **\[** ***or up-arrow in front of a character to keep it in uppercase.*** ***Standard I/O for*** ***the command uses the*** **xtrs** ***program's standard I/O descriptors; it does not go to the TRS-80 screen or come*** ***from the TRS-80 keyboard.*** - *Note:* ***The execution of Unix shell commands may be prohibited by the*** **-emtsafe** ***flag; see*** **Options**, ***below.*** *MOUNT/CMD* ***(or*** *MOUNT6/CMD*) ***is a convenience program that switches emulated floppy disks in the drives.*** - ***Usage:*** **MOUNT** \[**-l**\] *unixfile unit-number* - ***The*** **-l** ***flag converts*** *unixfile* ***to lowercase.*** ***When using the*** **-l** ***flag, you can put a*** **\[** ***or up-arrow in front of a character to keep it in uppercase.*** *unixfile* ***is any Unix filename;*** *unit-number* ***is a single digit, 0 through 7.*** ***The command deletes the file*** *disk*M*-*U ***(where*** *M* ***is the TRS-80 model and*** *U* ***is the given*** *unit-number*) ***from the disk directory (see the*** **-diskdir** ***option below), replaces it with a symbolic link to the given filename, and*** ***signals a disk change (as if*** **F7** ***had been pressed).*** - *Note:* ***The mounting of a Unix file as a disk image may be prohibited by the*** **-emtsafe** ***flag; see*** **Options**, ***below.*** *UMOUNT/CMD* ***(or*** *UMOUNT6/CMD*) ***is a convenience program that removes an emulated floppy disk from a drive.*** - ***Usage:*** **UMOUNT** *unit-number* - *unit-number* ***is a*** ***single digit, 0 through 7.*** ***The command deletes the file*** *disk*M*-*U ***(where*** *M* ***is the TRS-80 model and*** *U* ***is the given*** *unit-number*) ***from the disk directory (see the*** **-diskdir** ***option below), and signals a disk change (as if*** **F7** ***had been pressed).*** - *Note:* ***The unmounting of a Unix file as a disk image by deleting it on the host may be*** ***prohibited by the*** **-emtsafe** ***flag; see*** **Options**, ***below.*** ***The emulated floppy*** *cpmutil.dsk* ***contains import and export programs for Montezuma*** *CP/M*, ***written by Roland Gerlach.*** ***It was formatted as a “Montezuma Micro Standard DATA disk (40T, SS, DD,*** ***200K)”, with 512-byte sectors.*** ***Be careful to configure your*** *CP/M* ***to the proper disk format and drive parameters (40 tracks, not 80), or you will*** ***have confusing problems reading this disk.*** ***Documentation is included in the file*** *cpmutil.html* ***and source code in the file*** *cpmutil.tgz* ***(a gzipped tar archive) in the*** **xtrs** ***source distribution.*** ***The emulator implements a set of pseudo-instructions (emulator traps) that give*** ***TRS-80 programs access to Unix files.*** ***The programs listed above use them.*** ***If you would like to write your own such programs, the traps are documented in*** ***the file*** *trs\_imp\_exp.h*. ***Assembler source code for the existing programs is supplied in*** *xtrshard.z*, *import.z*, *export.z*, ***and*** *settime.z*. ***You can also write programs that use the traps in Misosys C, using the files*** *xtrsemt.h* ***and*** *xtrsemt.ccc* ***as an interface; a simple example is in*** *settime.ccc*. ***All of these files are available in the*** **xtrs** ***source distribution.*** ### Interrupts ***The emulator supports only interrupt mode 1 of the Z80.*** ***It will complain if your program enables interrupts after powerup without*** ***executing an IM 1 instruction first.*** ***All Model I/III/4/4P software does this, as the built-in peripherals in these*** ***machines support only IM 1.*** ***The Model I has a 40 Hz heartbeat clock interrupt, while the Model III uses 30*** ***Hz, and the Model 4/4P can run at either 30 Hz or 60 Hz.*** ***The emulator has a notion of the absolute time at which each tick is supposed to*** ***occur, and it asks the host system to wake it up at each of those times.*** ***The net result is that some ticks may be late, but there are always the proper*** ***number of ticks per second.*** ***For example, running in Model I mode on a Linux kernel configured with HZ=100,*** ***you'd see this pattern: (tick, 30ms, tick, 20ms, ...) instead of a tick every*** ***25ms.*** ### Processor speed selection ***A standard Model 4 has a software-controlled switch to select operation at*** ***either 4.05504 MHz (with heartbeat clock at 60 Hz) or 2.02752 MHz (with*** ***heartbeat clock at 30 Hz).*** **xtrs** ***emulates this feature.*** ***Model I machines were often modified to operate at higher speeds than the*** ***standard 1.77408 MHz.*** ***With one common modification, writing a 1 to port 0xFE would double the speed to*** ***3.54816 MHz, while writing a 0 would set the speed back to normal.*** ***The heartbeat clock runs at 40 Hz in either case.*** **xtrs** ***emulates this feature as well.*** ### Sound ***Sound support uses the Open Sound System (OSS)*** */dev/dsp* ***device, standard on Linux and available on many other Unix versions as well.*** ***This support is compiled in automatically on Linux; if you have OSS on another*** ***version of Unix, you'll need to define the symbol*** **HAVE\_OSS** ***in the source distribution's*** *Makefile* ***or in*** *trs\_cassette.c*. ***Any time TRS-80 software tries to write non-zero values to the cassette port (or*** ***the Model 4/4P optional sound port) with the cassette motor off, it is assumed*** ***to be trying to make sounds and*** **xtrs** ***opens*** */dev/dsp*. ***It automatically closes the device again after a few seconds of silence.*** ***If you are playing a game with sound, you'll want to use the*** **-autodelay** ***flag to slow down instruction emulation to approximately the speed of a real*** ***TRS-80.*** ***If you don't do this, sound will still play correctly, but the gameplay may be*** ***way too fast and get ahead of the sound.*** ***On the other hand, if your machine is a bit too slow, you'll hear gaps and pops*** ***in the sound when the TRS-80 program lags behind the demand of the sound card*** ***for more samples.*** ***The*** **-autodelay** ***feature includes a small speed boost whenever a sound starts to play to try to*** ***prevent this, but if the boost is too much or too little, you might either find*** ***that the game runs too fast when a lot of sound is playing, or that the sound*** ***has gaps in it anyway.*** ***If your sound has gaps, you can try reducing the sample rate with the*** **-samplerate** ***flag.*** ***The Orchestra-85 music synthesis software will run under*** **xtrs**'s ***Model I emulation, and the Orchestra-90 software will run with Model III*** ***operating systems under*** **xtrs**'s ***Model III, 4, or 4P emulation.*** ***For best results, use Orchestra-90 and the Model 4 emulation, as this lets the*** ***software run at the highest emulated clock rate (4 MHz) and thus generate the*** ***best sound.*** ***If you want to run Orchestra-85 instead, you can tell it that you have a 3.5 MHz*** ***clock speedup with enable sequence 3E01D3FE and disable sequence 3E00D3FE; this*** ***will let the software run twice as fast as on an unmodified Model I and generate*** ***better sound.*** ***There is no need to use*** **xtrs**'s **-autodelay** ***flag when running Orchestra-85/90, but you might want to specify a small fixed*** ***delay to keep from getting excessive key repeat.*** ### Mouse ***A few Model 4 programs could use a mouse, such as the shareware hi-res*** ***drawing program*** *MDRAW-II*. ***The program*** *XTRSMOUS/CMD* ***on the utility disk*** (*utility.dsk*) ***is a mouse driver for Model 4/4P mode that should work with most such programs.*** **xtrs** ***does not emulate the actual mouse hardware (a serial mouse plugged into the*** ***Model 4 RS-232 port), so the original mouse drivers will not work under*** **xtrs**. ***Instead,*** *XTRSMOUS* ***accesses the X mouse pointer using an emulator trap.*** *XTRSMOUS* ***implements the same*** *TRSDOS*/*LS-DOS* ***6 SVC interface as the David Goben and Matthew Reed mouse drivers.*** ***(It does not implement the interface of the older Scott McBurney mouse driver,*** ***which may be required by some programs.)*** ***By default*** *XTRSMOUS* ***installs itself in high memory.*** ***This is done because*** *MDRAW-II* ***tests for the presence of a mouse by looking to see whether the mouse SVC is*** ***vectored to high memory.*** ***If the driver is installed in low memory,*** *MDRAW* ***thinks it is not there at all.*** ***If you use mouse-aware programs that don't have this bug, or if you edit the*** ***first line of*** *MDRAW* ***to remove the test, you can install*** *XTRSMOUS* ***in low memory under*** *TRSDOS*/*LS-DOS* ***6 using the syntax*** **XTRSMOUS (LOW)**. ### Time-of-day clock ***Several battery-backed time of day clocks were sold for the various TRS-80*** ***models, including the TimeDate80, TChron1, TRSWatch, and T-Timer.*** ***They are essentially all the same hardware, but reside at a few different port*** ***ranges.*** **xtrs** ***currently emulates them at port ranges 0x70–0x7C and 0xB0–0xBC.*** ***The T-Timer port range at 0xC0–0xCC conflicts with the Radio Shack hard drive*** ***controller and is not emulated.*** ***These clocks return only a 2-digit year, and it is not well-documented what*** ***their driver software does since the year 2000.*** ***If you have software that works with one of them, please contact the*** ***author*** ⟨http://\\:www.tim-mann.org/⟩ ***to report what happens when it is used with*** **xtrs**. ***Also see*** *SETTIME/CMD* ***in*** **Data import and export**, ***above, for another way to get the correct time into a Z80 operating system*** ***running under*** **xtrs**. ***Note that Model I*** *TRSDOS* ***and*** *VTOS* ***4.0 have a “year 1988” problem, and*** *LDOS*/*LS-DOS* ***has a “year 2012” problem; see*** *LDOS and LS-DOS: 2012 and Beyond — Technical information* ⟨http://\\:www.trs-80.org/\\:ldos-and-ls-dos-2012-and-beyond-technical-information/⟩ ***by Matthew Reed.*** ### Joystick ***Pressing a key on a PC-keyboard-style numeric keypad with*** **NumLock** ***disengaged emulates the Alpha Products joystick.*** ***See*** **Keys**, ***above, for details.*** ***The emulated joystick is mapped only at port 0, to avoid conflicts with other*** ***devices.*** ### Running games ***Some games run rather well under*** **xtrs** ***provided that your machine is fast enough to run the emulation in real time and*** ***that you choose the right command-line options.*** *Galaxy Invaders Plus* ***by Big 5 Software is particularly good.*** ***You will usually want to turn on autodelay, and if your machine is slow you may*** ***need to reduce the sound sample rate.*** ***Running your X server in 8-bit/pixel mode also seems to help in some cases.*** ***Example command lines:*** ``` $ startx -- -bpp 8 $ xtrs -autodelay ``` ***If you have a slow machine and the sound breaks up, it is possible that your*** ***machine is not fast enough to generate samples at the default rate of 44,100 Hz.*** ***If you think this may be happening, try*** **-samplerate 11025** ***or even*** **-samplerate 8000**. ## Options ***Defaults for all options can be specified using the standard X resource*** ***mechanism; see the*** ***Resource Manager Functions chapter of*** *Xlib — C Language X Interface* ⟨ftp://\\:www.x.org/\\:pub/\\:current/\\:doc/\\:libX11/\\:libX11/\\:libX11.html#\\:Resource\_Manager\_Functions⟩ ***by Jim Gettys, Robert W. Scheifler, et al.*** ***The class name for*** **xtrs** ***is*** **Xtrs**. **-display** *x-display* ***Set your X display to*** *x-display.* ***The default is to use the DISPLAY environment variable.*** **-iconic** ***Start with the*** **xtrs** ***window iconified.*** **-background** *color* - **-bg** **-fg** *color* ***Set the background color of the*** **xtrs** ***window to*** *color*. **-foreground** *color* *color* ***Set the foreground color of the*** **xtrs** ***window to*** *color*. **-title** *title-text* ***Use*** *title-text* ***in the window title bar instead of the program name.*** **-borderwidth** *width* ***Put a border of*** *width* ***pixels*** ***around the TRS-80 display.*** ***The default is 2.*** **-scale** *xfac*\[ **,***yfac* ***\]*** ***Multiply the horizontal and vertical window size by*** *xfac* ***and*** *yfac*, ***respectively.*** ***Possible values are integers in the range*** ***\[1,4\] for*** *xfac* ***and \[1,8\] for*** *yfac*. ***Defaults are*** *xfac*=1 ***and*** *yfac*=2×*xfac*. ***Ignored if*** **-usefont** ***is given.*** **-resize** ***In Model III or 4/4P mode, resize the X window whenever the emulated display*** ***mode changes between 64×16 text (or 512×192 graphics) and 80×24 text*** ***(or 640×240 graphics).*** ***This is the default in Model III mode, since 80×24 text is not available and*** ***the 640×240 graphics add-on card is seldom used.*** **-noresize** ***In Model III or 4/4P mode, always keep the X window large enough for 80×24*** ***text or 640×240 graphics, putting a blank margin around the outside when the*** ***emulated display mode is 64×16 text or 512×192 graphics.*** ***This is the default in Model 4/4P mode, since otherwise there is an annoying*** ***size switch during every reboot.*** **-charset** *charset-name* ***Select among several sets of built-in character bitmaps.*** ***Valid values of*** *charset-name* ***depend on the TRS-80 model being emulated.*** - ***In Model I mode, five sets are available.*** ***The default,*** **wider**, ***is a modified Model III set with characters 8 pixels wide; it looks better on a*** ***modern computer screen with square pixels than the real Model I fonts, which*** ***were 6 pixels wide.*** **lcmod** ***is the character set in the replacement character generator that was supplied*** ***with the Radio Shack lowercase modification.*** ***(It was reconstructed partly from memory and may have some minor bit errors.)*** **stock** ***is the character set in the stock character generator supplied with most*** ***uppercase-only machines.*** ***Since*** **xtrs** ***currently always emulates the extra bit of display memory needed to support*** ***lowercase, this character set gives you the authentic, unpleasant effect that*** ***real Model I users saw when they tried to do homebrew lowercase modifications*** ***without replacing the character generator: lowercase letters appear at an*** ***inconsistent height, and if you are using the Level II BASIC ROM display driver,*** ***uppercase letters are replaced by meaningless symbols.*** **early** ***is the same as stock, but with the standard ASCII characters \[, \\, \], and*** ***^ in the positions where most Model I machines had directional arrows.*** ***This was the default programming in the Motorola character generator ROM that*** ***Radio Shack used, and a few early machines were actually shipped with this ROM.*** ***Finally,*** **german** ***or*** **genie** ***gives an approximate emulation of the GENIE, a German Model I clone.*** ***Characters are 8 pixels wide, and double width is supported even though later*** ***GENIE models did not include it.*** - **-romfile3** **-romfile4p** ***In Model III, 4, and 4P modes, three sets are available:*** **katakana** ***(the default for Model III) is the original Model III set with Japanese Katakana*** ***characters in the alternate character positions.*** ***This set was also used in early Model 4 machines.*** **international** ***(the default for Model 4 and 4P) is a later Model 4 set with accented Roman*** ***letters in the alternate positions.*** **bold** ***is a boldface set from a character generator ROM found in one Model*** ***III—origin uncertain.*** **-usefont** ***Use X fonts instead of the built-in character bitmaps.*** **-nofont** ***Use the built-in character bitmaps, not an X font.*** ***This is the default.*** **-font** *font-name* ***If*** **-usefont** ***is also given, use the X font*** *font-name* ***for normal-width characters.*** ***The default uses a common X fixed-width font:*** ***"-misc-fixed-medium-r-normal--20-200-75-75-\*-100-iso8859-1".*** **-widefont** *font-name* ***If*** **-usefont** ***is also given, use the X font*** *font-name* ***for double-width characters.*** ***The default uses a common X fixed-width font, scaled to double width:*** ***"-misc-fixed-medium-r-normal--20-200-75-75-\*-200-iso8859-1".*** **-nomicrolabs** ***In Model I mode, emulate the HRG1B 384×192 hi-res graphics card.*** ***In Model III mode or Model 4/4P mode, emulate the Radio Shack hi-res card.*** ***This is the default.*** **-microlabs** ***In Model III or 4/4P mode, emulate the Micro Labs Grafyx Solution hi-res*** ***graphics card.*** ***Note that the Model III and Model 4/4P cards from Micro Labs are very different*** ***from one another.*** **-debug** ***Enter*** *zbx*, ***the Z80 debugger.*** **-romfile** *filename* *filename3* *filename4p* ***Use the ROM image file specified by*** *filename* ***in Model I mode,*** ***by*** *filename3* ***in Model III and Model 4 mode,*** ***or by*** *filename4p* ***in Model 4P mode.*** ***A ROM image file can be either a raw binary dump in Intel hex format, or*** ***TRS-80 CMD format (for example, a*** *MODELA/III* ***file).*** ***If you do not set this option or the corresponding X resource, a default*** ***established at compile time is used (if any); see*** *Makefile.local* ***in the*** **xtrs** ***source distribution*** ***for instructions on compiling in default ROM image files or default ROM image*** ***filenames.*** **-model** *m* ***Emulate a TRS-80 Model*** *m*. ***Values accepted are*** **1** ***or*** **I** ***(Model I),*** **3** ***or*** **III** ***(Model III),*** **4** ***or*** **IV** ***(Model 4), and*** **4P** ***or*** **IVP** ***(Model 4P).*** ***Model I is the default.*** **-delay** *d* ***Tune the emulator's (crude) speed control.*** ***After each Z80 instruction,*** **xtrs** ***busy-waits for*** *d* ***iterations around an empty loop.*** ***A really smart C optimizer might delete this loop entirely, so it's possible*** ***that this option won't work if*** **xtrs** ***is compiled with too high an optimization level.*** ***The default delay is 0.*** **-autodelay** ***Dynamically adjust the value of the speed control described in*** **-delay** ***above to run instructions at roughly the same rate as a real machine.*** ***The tracking is only approximate, but it can be useful for running games.*** **-noautodelay** ***Turn off*** **-autodelay**. ***This is the default.*** **-keystretch** *cycles* ***Fine-tune the keyboard behavior.*** ***To prevent keystrokes from being lost,*** **xtrs** ***“stretches” the intervals between key transitions, so that the Z80 program*** ***has time to see each transition before the next one occurs.*** ***Whenever the Z80 program reads the keyboard matrix and sees an emulated key go*** ***up or down,*** **xtrs** ***waits*** *cycles* ***Z80 clock cycles (T-states) before it allows the program to see another key*** ***transition.*** ***Key transitions that are received during the waiting period or when the Z80*** ***program is not reading the keyboard are held in a queue.*** ***The default stretch value is 4000 cycles; it should seldom if ever be necessary*** ***to change it.*** **-shiftbracket** ***Emulate \[, \\, \], ^ and \_ as shifted keys, and {, \|, }, and ~ as*** ***unshifted.*** ***This is the default in Model 4 and 4P modes, and it works well with the keyboard*** ***driver in Model 4*** *TRSDOS*/*LS-DOS* ***6.*** **-noshiftbracket** ***Emulate \[, \\, \], ^ and \_ as unshifted keys, and {, \|, }, and ~ as*** ***shifted.*** ***This is the default in Model I and III modes, and it works well with many TRS-80*** ***keyboard drivers.*** ***With some keyboard drivers these keys do not work at all, however.*** **-diskdir** *dir* ***Set the search directory for floppy and hard disk images to*** *dir*. ***If the value starts with “~/” (or is just “~”), it is relative*** ***to your home directory (as determined by the*** **HOME** ***environment variable).*** ***The default value is “.”.*** **-doubler** *doubler-type* ***(Model I mode only)*** ***Set the double-density adaptor to emulate to*** *doubler-type*. ***The parameter may be*** **percom**, **radioshack** ***(or*** **tandy**), **both**, ***or*** **none**. *doubler-type* ***may be abbreviated to one character.*** ***The default is*** **both**, ***which causes the double density adaptor emulation to respond to the special*** ***commands of both the Percom and Radio Shack cards.*** **-doublestep** ***(Linux only)*** ***Make all real floppy drives double-step, allowing access to 35-track or 40-track*** ***media in an 80-track drive.*** ***See*** **Bugs and limitations**, ***below.*** **-nodoublestep** ***(Linux only)*** ***Turn off double-step mode for all real floppy drives.*** ***This is the default.*** **-stepmap** *s0*\[ **,***s1* ***\[*****,***s2* ***\[*****,***s3* ***\[*****,***s4* ***\[*****,***s5* ***\[*****,***s6* ***\[*****,***s7* ***\]\]\]\]\]\]\]*** ***(Linux only)*** ***Selectively set double-step mode for individual real floppy drives.*** ***Each comma-delimited parameter corresponds to a drive unit number; see*** **Real floppy disks**, ***above.*** ***If*** *s*U ***is*** **1** ***and*** *disk*M*-*U ***is a (symbolic link to) a real drive,*** ***where*** *M* ***is the TRS-80 model*** (**1**, **3**, **4**, ***or*** **4p**) ***and*** *U* ***is the drive unit number (a digit in the range 0–7), the drive will be*** ***single-stepped; if*** *s*U ***is*** **2**, ***it will be double-stepped.*** ***You can omit values from the end of the list; those drives will get the*** ***default value set by*** **-doublestep** ***or*** **-nodoublestep**. - ***Example:*** **-model 1 -stepmap 2,1,2** ***double-steps*** *disk1-0* ***and*** *disk1-2*, ***and single-steps*** *disk1-1*. **-sizemap** *z0*\[ **,***z1* ***\[*****,***z2* ***\[*****,***z3* ***\[*****,***z4* ***\[*****,***z5* ***\[*****,***z6* ***\[*****,***z7* ***\]\]\]\]\]\]\]*** ***Selectively set whether drives are emulated as*** ***5******¼******-inch or 8-inch; see*** **Emulated 8-inch floppy disks**, ***above.*** ***If*** *zU* ***is*** **5**, ***the drive will appear to Z80 software as*** ***5******¼******-inch; if*** **8**, ***as 8-inch.*** ***The default setting (as reflected in the documentation above) is*** **5,5,5,5,8,8,8,8**. ***You can omit values from the end of the list; those drives will get the default*** ***values.*** ***Setting one or more of the first four drives to 8-inch may be useful for*** *CP/M* ***software that supports 8-inch drives.*** ***You can also use*** *XTRS8/DCT* ***with 8-inch drives in the first four positions; even though the prompt suggests*** ***the unit number must be 4–7, numbers 0–3 are accepted.*** *XTRS8* ***does not check whether the unit you've selected is really being emulated as an*** ***8-inch drive, however; you'll simply get errors during*** *FORMAT* ***if you get this wrong.*** **-truedam** ***Turn off the single density data address mark remapping kludges*** ***described in*** **Emulated floppy disks** ***and*** **Real floppy disks**, ***above.*** ***With this option given, the distinction between 0xF8 and 0xFA data address marks*** ***is strictly observed on both writing and reading.*** ***This option is probably not useful unless you need to deal with Model I disks*** ***that use the distinction as part of a copy-protection scheme.*** ***See also*** *Common File Formats for Emulated TRS-80 Floppy Disks* ⟨http://\\:www.tim-mann.org/\\:trs80/\\:dskspec.html⟩. **-notruedam** ***The opposite of*** **-truedam**. ***This setting is the default.*** **-samplerate** *rate* ***Set the sample rate for new cassette WAVE files, direct cassette I/O to the*** ***sound card, and game sound output to the sound card.*** ***Existing WAVE files will be read or modified using their original sample rate*** ***regardless of this flag.*** ***The default is 44,100 Hz.*** ***See also*** [**cassette**(1)](/cassette/1.md). **-serial** *terminal-name* ***Set the terminal device to be used for I/O to the TRS-80's serial port to*** *terminal-name.* ***The default is*** */dev/ttyS0* ***on Linux, and*** */dev/tty00* ***on other versions of Unix.*** ***Setting the name to be empty*** (**-serial ""**) ***emulates having no serial port.*** **-switches** *value* ***Set the sense switches on the Model I serial port card.*** ***This option is meaningful only in Model I mode, and only when the*** **-serial** ***option is not set to "".*** ***The default value is 0x6F, which Radio Shack software conventionally interprets*** ***as 9600 bps, 8 bits/word, no parity, 1 stop bit.*** **-emtsafe** ***Disable emulator traps (see*** **Data import and export**, ***above) that could write to host files other than disk images in the original*** ***emulated disk directory, or otherwise affect the host system (e.g., Unix shell*** ***commands).*** ***This setting is the default.*** **-noemtsafe** ***The opposite of*** **-emtsafe**. ## Exit status **xtrs** ***primarily uses diagnostic messages to indicate trouble.*** ***0*** ***Successful operation; normal or expected exit.*** ***1*** ***Fatal error; includes usage errors such as unrecognized command-line arguments.*** ***-1, 255*** ***Unable to open X display.*** ## Environment **xtrs** ***reads a couple of environment variables.*** **DISPLAY** ***is read indirectly via*** [**XOpenDisplay**(3)](/XOpenDisplay/3.md), ***and specifies the X server to which*** **xtrs** ***(an X client)*** ***should connect.*** **HOME** ***is used at startup to (1) locate*** *.Xdefaults* ***and*** *Xtrs* ***files specifying defaults for command-line options and (2) resolve the argument*** ***to the*** **-diskdir** ***option;*** ***and sometimes when the emulator trap to change*** **xtrs**'s ***current working directory is activated; see*** **Data import and export**, ***above.*** ## Files **xtrs** ***may access files as described under*** **HOME** ***in*** **Environment**, ***above, as well as floppy drive, digital signal processor (sound), and terminal*** ***device files; see*** **Real floppy disks** ***and*** **Sound**, ***above, and*** **-serial** ***under*** **Options**, ***above.*** ***If the*** **-emtsafe** ***flag is not in effect, then through the use of emulator traps*** ***(see*** **Data import and export**, ***above)*** *arbitrary* ***files on the system may be read, written, or deleted from within the emulator*** ***with the privileges of the user invoking*** **xtrs**. ## Bugs and limitations ***The emulated serial port's modem status and control signals are not tied to the*** ***signals on the real serial port, because the real signals are not available to*** ***software through the Unix terminal device interface.*** ***The ability to check for parity, framing, and overrun errors and receive an*** ***interrupt when one occurs is not emulated.*** ***Unix does not support 2000, 3600, or 7200 baud, so these TRS-80 data rates are*** ***remapped to 38400, 57600, and 115200 baud respectively.*** ***A better signal processing algorithm might help read real cassettes more*** ***reliably, especially at 1500bps.*** ***Some features of the floppy disk controller are not currently emulated.*** - • ***Force Interrupt with condition bits 0x01, 0x02, or 0x04 is not implemented.*** - • ***Read Track is implemented only for DMK emulated floppies.*** - • ***The multiple-sector flags in Read and Write are not implemented.*** - • ***The timing of returned sectors is emulated only for the Read Address command,*** ***and not very accurately for JV1 or JV3.*** - • ***If a disk has more than one sector with the same number on a track,*** **xtrs** ***will always see the first (counting from the index hole) when reading or*** ***writing; a real machine would see the next one to come under the head depending*** ***on the current rotational position of the disk.*** ***Partially reformatting a track (which TRS-80 programs like*** *HyperZap* ***and Model I*** *Super Utility* ***do to achieve mixed density) is supported for DMK but not JV3; however,*** ***switching densities while formatting (which Model III and 4*** *Super Utility* ***do) works on both DMK and JV3.*** ***Real physical floppy disks are supported only under Linux, because Unix does not*** ***define a portable interface to the low-level floppy controller functionality*** ***that*** **xtrs** ***needs.*** ***There are some limitations even under Linux: index holes are faked, not detected*** ***on the real disk, and the timing of returned sectors is not emulated at all.*** ***Due to the limitations of ISA-bus floppy disk controllers, when formatting a*** ***physical floppy under*** **xtrs**, ***you cannot mix sectors of different sizes on the same track, switch densities in*** ***the middle of a track, or reformat only part of a track.*** ***However,*** **xtrs** ***can read and write to physical floppies that have already been formatted in*** ***these ways (perhaps by a real TRS-80).*** ***The extended JV3 limit of 5802 sectors is somewhat arbitrary.*** ***It could be raised by generalizing the code to permit more than two blocks of*** ***2901, but this does not seem too useful.*** ***5802 sectors is already enough for a*** ***3******½******-inch HD (1.44MB) floppy, which the TRS-80 didn't support anyway.*** ***If you need more space, use emulated hard drives instead of emulated floppies*** ***with huge numbers of tracks.*** *XTRSHARD/DCT* ***ignores the internal write-protected flag in hard drive images, but a hard drive*** ***image can still be effectively write protected by turning off its Unix write*** ***permission bits.*** ***The emulator uses a heuristic to decide what format a ROM image file is in.*** ***If a raw binary ROM image starts with 0x01, 0x05, or 0x22, it can be*** ***misidentified as being in a different format.*** ***This is rather unlikely to occur, as ROMs typically begin with 0xF3, the DI*** ***instruction.*** ***The joystick emulation could be made to work with real joysticks using the X*** ***Input extension, but this is not implemented yet.*** ***If you discover other bugs, write fixes for any of these, or make any other*** ***enhancements, please let us know so that we can incorporate the changes into*** ***future releases.*** ## Authors and acknowledgements **xtrs** ***1.0 was written by David Gingold and Alec Wolman.*** ***The current version was revised and much extended by Timothy Mann*** ***(see*** ⟨http://\\:www.tim-mann.org/⟩). ***See*** *README* ***in the*** **xtrs** ***source distribution for additional notes from the authors; a (compressed) copy*** ***may be locally available with your*** **xtrs** ***installation at*** */usr/share/doc/xtrs/README.gz*. ***We also thank the following people for their help.*** ***The JV1 and JV3 floppy disk file formats were designed by Jeff Vavasour,*** ***originally for his*** *MS-DOS*-based ***TRS-80 emulators.*** ***The DMK format was designed by David Keil for his*** *MS-DOS*-based ***TRS-80 emulator.*** ***The hard disk file format was designed by Matthew Reed for his*** *MS-DOS*-based ***TRS-80 emulators.*** ***Al Petrofsky and Todd P. Cromwell III supplied font data.*** ***Roland Gerlach contributed the*** *CP/M* ***import and export programs as well as several bug reports and fixes for the*** ***emulator itself.*** ***Ulrich Mueller added the*** **-borderwidth** ***option, improved the*** **-scale** ***option and the bitmap font scaling, ported the*** *IMPORT*, *EXPORT*, ***and*** *SETTIME* ***utilities to*** *NEWDOS/80*, ***and contributed the HRG1B emulation.*** ***Branden Robinson supplied the first version of the cassette man page, fixed*** ***Makefile bugs, translated cassette to the Bourne shell, and implemented*** ***watchpoints in*** *zbx*. ***Mark McDougall provided documentation for the Micro Labs Grafyx Solution card.*** ***Jenz Guenther added the*** **-title** ***option and contributed code to emulate the GENIE (German Model I clone).*** ***Joe Peterson contributed code to emulate the TimeDate80 and the*** **-emtsafe** ***feature.*** ***Denis Leconte contributed part of the*** **-scale** ***implementation.*** ## See also [**cmddump**(1)](/cmddump/1.md), [**hex2cmd**(1)](/hex2cmd/1.md), [**cassette**(1)](/cassette/1.md), [**mkdisk**(1)](/mkdisk/1.md) ***There are many other TRS-80 resources available on the Web, including shareware*** ***and freeware emulators that run under*** *MS-DOS* ***and other operating systems,*** ***software for converting TRS-80 physical media to the emulator's disk file*** ***format, ROM images, and TRS-80 software that has already been converted.*** ***For pointers, see*** ⟨http://\\:www.tim-mann.org/\\:trs80.html⟩.