29 Aug
2025
29 Aug
'25
3:50 p.m.
I've been using a modified version of ttymidi with fair success while
using JackD2, but have now migrated to
using pipewire. Despite having pipewire-jack installed and working,
ttymidi no longer works with it.
Basically it is converting midi events which come from Arduinos using
the USB port, which looks like a serial
port. ttymidi receives events and packs them into jack buffers.
Similarly any jack midi events being issued by jack
are copied onto the serial port.
Does anyone have any help to offer?
Bill
--
+---------------------------------------------+
| Bill Purvis G8DIO |
|bill(a)billp.org |
+---------------------------------------------+
30 Aug
30 Aug
9:07 a.m.
On 8/29/25 17:50, Bill Purvis wrote:
I've been using a modified version of ttymidi with
fair success while
using JackD2, but have now migrated to
using pipewire. Despite having pipewire-jack installed and working,
ttymidi no longer works with it.
If it's modified, maybe the standard version is better to test? Out of
curiosity, I downloaded the source code and compiled. Not that I have
any MIDI stuff running on the serial port right now so I can't test it,
but it shows up as alsa-midi in qpwgraph.
id 116, type PipeWire:Interface:Port/3
object.serial = "33446"
object.path = "alsa:seq:default:client_129:playback_1"
format.dsp = "8 bit raw midi"
node.id = "42"
port.id = "2"
port.name = "ttymidiMIDI in (playback)"
port.direction = "in"
port.alias = "ttymidi:MIDI in"
port.group = "client_129"
id 154, type PipeWire:Interface:Port/3
object.serial = "33445"
object.path = "alsa:seq:default:client_129:capture_0"
format.dsp = "8 bit raw midi"
node.id = "42"
port.id = "2"
port.name = "ttymidiMIDI out (capture)"
port.direction = "out"
port.alias = "ttymidi:MIDI out"
port.group = "client_129"
--
/bengan
9:48 a.m.
On 30/08/2025 10:07, Bengt Gördén wrote:
On 8/29/25 17:50, Bill Purvis wrote:
Well, I have tweaked various
bits to handle special cases - I use the
Arduinos as scanners in an organ, so I need to distinguish between
them - no good connecting the pedal scanner to the tab stops! I do this
by identifying the channel on which they send - each has a dedicated
channel, and when first starting up it sends a dummy note-off with note
0. The modified ttymidi opens the serial port, and reads the first
event and decides from that what name to use when opening the jack port.
I've also cut out some of the more complex handling as the scanners
only ever send note-on and note-off, apart from the swell pedal scanner
which send parameter-change events. No complications with sysex request!
I'll have to download the original version again, and see how it
behaves. I've got various keyboards etc. that I can use for initial testing.
Many thanks for your troubles on my behalf!
Bill
--
+---------------------------------------------+
| Bill Purvis G8DIO |
| bill(a)billp.org |
+---------------------------------------------+
I've been using a modified version of ttymidi
with fair success while
using JackD2, but have now migrated to
using pipewire. Despite having pipewire-jack installed and working,
ttymidi no longer works with it.
If it's modified, maybe the standard version is better to test? Out of
curiosity, I downloaded the source code and compiled. Not that I have
any MIDI stuff running on the serial port right now so I can't test
it, but it shows up as alsa-midi in qpwgraph.
id 116, type PipeWire:Interface:Port/3
object.serial = "33446"
object.path = "alsa:seq:default:client_129:playback_1"
format.dsp = "8 bit raw midi"
node.id = "42"
port.id = "2"
port.name = "ttymidiMIDI in (playback)"
port.direction = "in"
port.alias = "ttymidi:MIDI in"
port.group = "client_129"
id 154, type PipeWire:Interface:Port/3
object.serial = "33445"
object.path = "alsa:seq:default:client_129:capture_0"
format.dsp = "8 bit raw midi"
node.id = "42"
port.id = "2"
port.name = "ttymidiMIDI out (capture)"
port.direction = "out"
port.alias = "ttymidi:MIDI out"
port.group = "client_129"
10:24 a.m.
On 30/08/2025 10:48, Bill Purvis wrote:
On 30/08/2025 10:07, Bengt Gördén wrote:
That's very interesting - I did a google search for 'ttymidi
source' and
got a selection of hits. Downloaded one, compiled and tested it to
find it hits the same errors as mine. Searched further and try a
different one, and that one seems to work.
The difference is: the one that works interfaces with libasound, rather
than direct with jack. I doubt if libasound had been invented when I
downloaded the original ttymidi. Just need to familiarise myself with
the libasound interface and fit my mods into this version.
The one that I downloaded and works is from:
http://www.varal.org/ttymidi/
Chrome is a bit reluctant to download from a http source, but it seems
to be OK. It's a tar.gz download, and comes with some arduino code as
well, which I have not explored. Anyone familiar with Midi and Arduinos
will have no problem getting it all to work.
Many, many thanks!
Bill
--
+---------------------------------------------+
| Bill Purvis G8DIO |
| bill(a)billp.org |
+---------------------------------------------+
On 8/29/25 17:50, Bill Purvis wrote:
Well, I have tweaked various
bits to handle special cases - I use the
Arduinos as scanners in an organ, so I need to distinguish between
them - no good connecting the pedal scanner to the tab stops! I do
this by identifying the channel on which they send - each has a dedicated
channel, and when first starting up it sends a dummy note-off with
note 0. The modified ttymidi opens the serial port, and reads the first
event and decides from that what name to use when opening the jack
port. I've also cut out some of the more complex handling as the scanners
only ever send note-on and note-off, apart from the swell pedal
scanner which send parameter-change events. No complications with
sysex request!
I'll have to download the original version again, and see how it
behaves. I've got various keyboards etc. that I can use for initial
testing.
Many thanks for your troubles on my behalf!
Bill I've been using a modified version of ttymidi
with fair success
while using JackD2, but have now migrated to
using pipewire. Despite having pipewire-jack installed and working,
ttymidi no longer works with it.
If it's modified, maybe the standard version is better to test? Out
of curiosity, I downloaded the source code and compiled. Not that I
have any MIDI stuff running on the serial port right now so I can't
test it, but it shows up as alsa-midi in qpwgraph.
id 116, type PipeWire:Interface:Port/3
object.serial = "33446"
object.path = "alsa:seq:default:client_129:playback_1"
format.dsp = "8 bit raw midi"
node.id = "42"
port.id = "2"
port.name = "ttymidiMIDI in (playback)"
port.direction = "in"
port.alias = "ttymidi:MIDI in"
port.group = "client_129"
id 154, type PipeWire:Interface:Port/3
object.serial = "33445"
object.path = "alsa:seq:default:client_129:capture_0"
format.dsp = "8 bit raw midi"
node.id = "42"
port.id = "2"
port.name = "ttymidiMIDI out (capture)"
port.direction = "out"
port.alias = "ttymidi:MIDI out"
port.group = "client_129" 
10:47 a.m.
On Sat, Aug 30, 2025 at 11:24:47AM +0100, Bill Purvis wrote:
The difference is: the one that works interfaces with
libasound, rather than
direct with jack. I doubt if libasound had been invented when I
downloaded the original ttymidi.
???
Libasound provides the standard API for ALSA. It has nothing at all
to do with Jack. It has existed for as long as ALSA has existed.
Ciao,
--
FA
10:59 a.m.
On 8/30/25 12:24, Bill Purvis wrote:
The one that I downloaded and works is from:
http://www.varal.org/ttymidi/
That's the one I used.
Bit of a CPU hog though.
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
bengan 304127 100 0.0 21144 3012 pts/5 Sl+ 10:23 153:18
./ttymidi -s /dev/ttyS0 -b 2400
--
/bengan
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linux-audio-user@lists.linuxaudio.org
5 comments
3 participants
participants (3)
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Bengt Gördén -
Bill Purvis -
Fons Adriaensen