159 lines
5.3 KiB
Markdown
159 lines
5.3 KiB
Markdown
# mustang-midi-bridge
|
|
|
|
Allow Fender Mustang series guitar amplifiers to be controlled by MIDI
|
|
messages
|
|
|
|
# What's New
|
|
|
|
The command line parameter for MIDI controller port is now assumed to
|
|
start at 0 rather than 1 in order to match the way Linux ALSA
|
|
enumerates devices (see 'Run' below).
|
|
|
|
The program has been updated to run as a non-privileged daemon
|
|
process. You can still invoke it on the command line, but there will
|
|
be no output to the console and it no longer responds to keypress
|
|
input. Enter Ctrl-C (SIGINT) to exit.
|
|
|
|
I have added the first version of a runtime framework that starts and
|
|
stops the program automatically based on attached MIDI devices. This
|
|
seems to be working on a Beaglebone SBC, but has not been extensively
|
|
tested or documented yet. There is a small amount of customization
|
|
required to account for your specific amp model and MIDI controller
|
|
interface. Technically oriented users can probably work this out,
|
|
otherwise wait a bit until I can refine the packaging and arrange to
|
|
have the various pieces configured from a common setup file.
|
|
|
|
Support added for amp and effects models specific to the Mustang v2
|
|
products. This has had only limited testing.
|
|
|
|
Added a python script to exercise the bridge.
|
|
|
|
# Introduction
|
|
|
|
The intent is to implement the published MIDI spec for the Fender
|
|
Mustang Floor pedal with whatever extensions are necessary to expose
|
|
features added to the 'v2' series.
|
|
|
|
I am developing on a Ubuntu Precise desktop machine, but the code is
|
|
routinely tested on a Raspberry Pi 'B' and Beagelbone Green to ensure
|
|
these remain viable deployment targets. At this point I'm still
|
|
experiencing issues with USB latency on the RPi and am currently
|
|
recommending the BBG for real-world use.
|
|
|
|
A special thanks to the original developer and contributors to 'PLUG',
|
|
from whence the Mustang USB interface code is stolen.
|
|
|
|
## For the non-techies
|
|
|
|
I have written a Wiki page here:
|
|
|
|
https://github.com/snhirsch/mustang-midi-bridge/wiki/Install
|
|
|
|
that attempts to walk less technical users through the installation
|
|
and build process on Raspberry Pi or Beaglebone. It's hard to know
|
|
what level of detail to hit and suggestions or comments would be
|
|
appreciated if I've omitted or glossed over something critical.
|
|
|
|
# Status
|
|
|
|
The Mustang Floor MIDI spec is about 99% implemented, with only the
|
|
following exceptions:
|
|
|
|
+ Tuner On/Off
|
|
|
|
Will require substantial rework of the program to make this work
|
|
reliably.
|
|
|
|
+ Amp Bypass
|
|
|
|
It's possible to turn the amp "off" with CC#68 0, but this mutes
|
|
all sound rather than acting as a bypass. I don't think the combo
|
|
amps support signal bypass, but haven't given up yet.
|
|
|
|
+ Pedal Volume
|
|
|
|
I'm not sure why this is needed, since all continuous controllers
|
|
are directly accessible through CC messages. Since the FUSE
|
|
application cannot issue these commands it will be guesswork to
|
|
figure out the protocol - if it's even supported on the combo
|
|
amps.
|
|
|
|
+ FX Insert
|
|
|
|
Not supported on the combo amps
|
|
|
|
+ Tap Tempo
|
|
|
|
If I can figure out how to do this from FUSE I can code it.
|
|
|
|
I'm using USBPcap and tshark to snoop communication and plan to
|
|
implement all features accessible from the Fender FUSE application.
|
|
However, some targets listed in the MIDI spec (e.g. amplifier on/off,
|
|
tuner mode) are not controllable from FUSE and it may take some time
|
|
and luck to figure out the protocol.
|
|
|
|
# Prerequisites
|
|
|
|
+ For Ubuntu Precise or Debian Jessie:
|
|
|
|
- libasound2
|
|
- librtmidi-dev
|
|
- libusb-1.0-0-dev
|
|
- libjack0 (Precise)
|
|
- libjackQ (Jessie)
|
|
|
|
Would appreciate feedback on requirements for other distributions.
|
|
|
|
# OS Configuration
|
|
|
|
+ Add the id of the user who will be running the bridge to the
|
|
'audio' and 'plugdev' groups. That user should then log out and back
|
|
in to make the groups effective.
|
|
|
|
+ As root, copy the file '50-mustang.rules' to /etc/udev/rules.d and
|
|
refresh the system with 'udevadm control --reload'.
|
|
|
|
There may be slight differences in requirements for other distributions.
|
|
|
|
# Build
|
|
```
|
|
$ make opt
|
|
```
|
|
or
|
|
```
|
|
$ make debug
|
|
```
|
|
as appropriate
|
|
|
|
# Run
|
|
|
|
Both the amplifier and MIDI source should be connected first, then:
|
|
```
|
|
$ mustang_midi midi_port# midi_listen_channel#
|
|
```
|
|
NOTE1: I'm not sure about other platforms, but on Linux the MIDI
|
|
port number is equivalent to the ALSA card index. I had originally
|
|
treated port as 1..n, but since ALSA (and JACK? Not sure..) starts at
|
|
0, this has now been changed. You can find the card index for your
|
|
controller by connecting it to the computer and examining the
|
|
pseudo-file, e.g.:
|
|
|
|
$ cat /proc/asound/cards
|
|
0 [PCH ]: HDA-Intel - HDA Intel PCH
|
|
HDA Intel PCH at 0xf7530000 irq 30
|
|
1 [Interface ]: USB-Audio - USB MS1x1 MIDI Interface
|
|
M-Audio USB MS1x1 MIDI Interface at usb-0000:00:14.0-1, full speed
|
|
|
|
To accept MIDI messages from devices behind the M-Audio interface you
|
|
would now specify '1' as the MIDI port value.
|
|
|
|
NOTE2: RPi and BBG are a bit fussy about enumeration of new USB
|
|
devices. If you are not getting proper communication, quit the program
|
|
and try replugging both the Fender amp and MIDI controller **after**
|
|
those devices are powered up.
|
|
|
|
NOTE3: I've had success using a passive USB hub with the single USB on
|
|
the BBG, but YMMV since most USB<->5Pin MIDI converters draw some
|
|
degree of bus power. A powered hub might be necessary in some
|
|
situations.
|
|
|