Update README

README.md

@@ -10,34 +10,61 @@ Mustang Floor pedal with whatever extensions are necessary to expose
 features added to the 'v2' series. Currently only patch change and
 effects on/off are implemented.
 
-Intended to build on Linux systems with the idea of deploying on
-RaspberryPi.
+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 USB interface code is stolen.
+from whence the Mustang USB interface code is stolen.
 
 # Prerequisites
 
-I'm working on Ubuntu Precise, YMMV for other distributions.
+  + For Ubuntu Precise or Debian Jessie:
 
-  + libjack-dev
-  + librtmidi-dev (2.0.1 - May need changes for newer versions)
-  + libusb-1.0
+    - 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#_
+```
+NOTE: 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.
 
+NOTE2: 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.