---
name: "oss_madi"
section: "7"
platform: "linux"
package: "oss4-base"
version: "4.2-build2010-2"
release: "Debian 8 (Jessie)"
platforms: ["linux"]
url: "https://new.carta.tech/oss_madi"
---

# oss\_madi(7)

RME HDSP MADI and AES32 audio driver

## NAME

**oss\_madi** - RME HDSP MADI and AES32 audio driver

## DESCRIPTION

**Open Sound System driver for RME HDSP MADI and AES32 audio interfaces.**

**This driver has been developed for RME HDSP MADI but it also supports** **HDSP AES32. The driver has been tested under Linux and Solaris under x86** **and Sparc.**

**The internal engine of the card supports 64 playback channels and 64 recording** **channels. Only the first channels are connected to the actual input and** **output ports of the card.**

**The mixer section of the card has recording level settings for all inputs.** **There is also an output mixer. Each output channel has mixer sliders for** **corresponding input channel and corresponding audio playback channel.**

**There is a full 64x(64+64) mixing matrix supported by the hardware. For** **the time being this mixer matrix cannot be accessed directly by the** **applications. However support for the SNDCTL\_MIX\_MATRIX\_WRITE and** **SNDCTL\_MIX\_MATRIX\_READ ioctl calls can be added in the future.**

## DEVICE FILES

**By default the driver will create input and output device files for** **each 32 stereo pairs. This can be changed by editing the settings in** **oss\_madi.conf (see below).**

**The application can set the devices to use 1, 2, 4, 8, 16, 32 or 64 channels.** **The device file being used selects the first channel slot within the available** **channels. For example pcm0 and pcmin0 sill select channel 0. Equally well** **pcm1 and pcmin1 will select channel slot 2 (assuming that madi\_devsize option** **is set to 2). The first device (pcm0 and pcmin0) can be set to use up to 64** **channels. The last devices (pcm31 and pcmin31) only support 1 or 2 channel mode.** **The other device files support channel configurations where the last channel** **doesn't exceed the number of total channels (madi\_maxchannels). Also the driver** **will not let two device files to share any of the channels with some other** **open device file.**

**This channel allocation mechanism gives maximum flexibility to the user. It is** **possible to use some output channels by multi channel application while the** **others are available for other applications. This works as long the channel** **allocations by different applications don't overlap.**

## OPTIONS

- **o madi\_maxchannels**

  **Number of channels supported by the driver. The default** **is 64 which is also the maximum. This parameter can** **be set to a lower value if full 64 channels are not** **required. With less channels the mixer/control panel** **interface will require less space on screen.**

- **o madi\_devsize**

  **By default this parameter is set to 2 which means that** **a device file will be created for each stereo channel** **pair. Possible values are 1, 2, 4, 8, 16, 32 or 64.**

## LIMITATIONS

- •

  **The current driver doesn't support all control panel features of the card.** **For example sampling rate is fixed to 48 kHz. More features will be added** **on contract.**

- •

  **Use of mmap() is and will not be supported.**

- •

  **Virtual mixer is not supported (yet).**

## FILES

**/etc/oss4/conf/oss\_madi.conf Device configuration file.**

## AUTHOR

**4Front Technologies**