XFM Updated to 1.02

This release includes a few improvements and additions:

Extensive MIDI System Exclusive Messages support

Every parameter in XFM can now be controlled via MIDI Sysex messages.
The format for the messages is as follows:

F0 42 UU PP PP VV VV F7

UU = Unit number (corresponds to the MIDI Channel XFM is set to receive)
PP = Parameter number, 0-247 (in two 7-bit values)
VV = Parameter Value, 0-255 (in two 7-bit values)

Examples:

% Turns OP1 on
F0 42 00 00 01 00 01 F7

% Turns OP2 level to 255
F0 42 00 00 23 01 7F F7

A few utility functions can also be called via Sysex:

% Initialize Program
F0 42 00 01 79 00 00 F7 

(the value bytes don’t matter)

% Read Program from EEPROM
F0 42 00 01 7A 00 05 F7

value = program number, in this case 5.

% Write Program to EEPROM
F0 42 00 01 7B 00 19 F7

value = program number, in this case 25 (19 hex)

Stereo Decimator Effect

Because who needs higher samplerates? 🙂 A new lo-fi stereo sample rate decimator can be now applied to XFM output (parameter 175).

I2S Audio Out

A few builders expressed their interest in interfacing XFM with an external DAC in order to build multi-module structures. I squeezed the silicon and had this in the unused connector of the Mojo!

Pinout is as follows:

P66 = System Clock (6.144 MHz)
P74 = Bit Clock (3.072 MHz for stereo, 32-bit I2S operation
P78 = Word Select
P80 = Data

P57 remains as MIDI Thru (a buffered connection from the MIDI in), which allows to daisy-chain modules.

Any feedback welcome. Enjoy!