1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
89 lines
4.0 KiB
Plaintext
89 lines
4.0 KiB
Plaintext
|
|
Serial UART 16450/16550 MIDI driver
|
|
===================================
|
|
|
|
The adaptor module parameter allows you to select either:
|
|
|
|
0 - Roland Soundcanvas support (default)
|
|
1 - Midiator MS-124T support (1)
|
|
2 - Midiator MS-124W S/A mode (2)
|
|
3 - MS-124W M/B mode support (3)
|
|
4 - Generic device with multiple input support (4)
|
|
|
|
For the Midiator MS-124W, you must set the physical M-S and A-B
|
|
switches on the Midiator to match the driver mode you select.
|
|
|
|
In Roland Soundcanvas mode, multiple ALSA raw MIDI substreams are supported
|
|
(midiCnD0-midiCnD15). Whenever you write to a different substream, the driver
|
|
sends the nonstandard MIDI command sequence F5 NN, where NN is the substream
|
|
number plus 1. Roland modules use this command to switch between different
|
|
"parts", so this feature lets you treat each part as a distinct raw MIDI
|
|
substream. The driver provides no way to send F5 00 (no selection) or to not
|
|
send the F5 NN command sequence at all; perhaps it ought to.
|
|
|
|
Usage example for simple serial converter:
|
|
|
|
/sbin/setserial /dev/ttyS0 uart none
|
|
/sbin/modprobe snd-serial-u16550 port=0x3f8 irq=4 speed=115200
|
|
|
|
Usage example for Roland SoundCanvas with 4 MIDI ports:
|
|
|
|
/sbin/setserial /dev/ttyS0 uart none
|
|
/sbin/modprobe snd-serial-u16550 port=0x3f8 irq=4 outs=4
|
|
|
|
In MS-124T mode, one raw MIDI substream is supported (midiCnD0); the outs
|
|
module parameter is automatically set to 1. The driver sends the same data to
|
|
all four MIDI Out connectors. Set the A-B switch and the speed module
|
|
parameter to match (A=19200, B=9600).
|
|
|
|
Usage example for MS-124T, with A-B switch in A position:
|
|
|
|
/sbin/setserial /dev/ttyS0 uart none
|
|
/sbin/modprobe snd-serial-u16550 port=0x3f8 irq=4 adaptor=1 \
|
|
speed=19200
|
|
|
|
In MS-124W S/A mode, one raw MIDI substream is supported (midiCnD0);
|
|
the outs module parameter is automatically set to 1. The driver sends
|
|
the same data to all four MIDI Out connectors at full MIDI speed.
|
|
|
|
Usage example for S/A mode:
|
|
|
|
/sbin/setserial /dev/ttyS0 uart none
|
|
/sbin/modprobe snd-serial-u16550 port=0x3f8 irq=4 adaptor=2
|
|
|
|
In MS-124W M/B mode, the driver supports 16 ALSA raw MIDI substreams;
|
|
the outs module parameter is automatically set to 16. The substream
|
|
number gives a bitmask of which MIDI Out connectors the data should be
|
|
sent to, with midiCnD1 sending to Out 1, midiCnD2 to Out 2, midiCnD4 to
|
|
Out 3, and midiCnD8 to Out 4. Thus midiCnD15 sends the data to all 4 ports.
|
|
As a special case, midiCnD0 also sends to all ports, since it is not useful
|
|
to send the data to no ports. M/B mode has extra overhead to select the MIDI
|
|
Out for each byte, so the aggregate data rate across all four MIDI Outs is
|
|
at most one byte every 520 us, as compared with the full MIDI data rate of
|
|
one byte every 320 us per port.
|
|
|
|
Usage example for M/B mode:
|
|
|
|
/sbin/setserial /dev/ttyS0 uart none
|
|
/sbin/modprobe snd-serial-u16550 port=0x3f8 irq=4 adaptor=3
|
|
|
|
The MS-124W hardware's M/A mode is currently not supported. This mode allows
|
|
the MIDI Outs to act independently at double the aggregate throughput of M/B,
|
|
but does not allow sending the same byte simultaneously to multiple MIDI Outs.
|
|
The M/A protocol requires the driver to twiddle the modem control lines under
|
|
timing constraints, so it would be a bit more complicated to implement than
|
|
the other modes.
|
|
|
|
Midiator models other than MS-124W and MS-124T are currently not supported.
|
|
Note that the suffix letter is significant; the MS-124 and MS-124B are not
|
|
compatible, nor are the other known models MS-101, MS-101B, MS-103, and MS-114.
|
|
I do have documentation (tim.mann@compaq.com) that partially covers these models,
|
|
but no units to experiment with. The MS-124W support is tested with a real unit.
|
|
The MS-124T support is untested, but should work.
|
|
|
|
The Generic driver supports multiple input and output substreams over a single
|
|
serial port. Similar to Roland Soundcanvas mode, F5 NN is used to select the
|
|
appropriate input or output stream (depending on the data direction).
|
|
Additionally, the CTS signal is used to regulate the data flow. The number of
|
|
inputs is specified by the ins parameter.
|