MIDI-Retrofit is an 8-channel MIDI-to-Trigger unit suitable for use with a variety of drum machines including the SDS range from Simmons for which it was originally designed.

Each of the TRIGGER outputs has velocity control and can be assigned to a specific MIDI Note and Channel using the `LEARN’ mode.

There are several options that can be selected using the onboard DIPSWITCH:-

1. DIPSWITCH #1 - TRIGGER INVERT - TRIGGER output pulses can either be positive-going (LO to HI) or negative-going (HI to LO). With DIPSWITCH #1 OFF the TRIGGER pulses are positive-going.
2. DIPSWITCH #2 - GATE MODE - When GATE MODE is OFF the TRIGGER outputs are set to generate a fixed width output pulse in response to a MIDI Note-ON command, in this mode the width of the output pulse is determined by the setting of the PLS WIDTH trimpot P301. When GATE Mode is ON the TRIGGER outputs turn ON with MIDI Note ON and turn OFF with MIDI Note OFF commands. .
3. DIPSWITCH #3 - ACCENT Mode - When ACCENT MODE is turned OFF all 8x TRIGGER outputs respond to their assigned MIDI Note/Channel. When ACCENT MODE is turned ON then some of the TRIGGER outputs become pre-assigned to an 'ACCENTED' output. See ACCENT TYPE for further definition.
4. DIPSWITCH #4 - ACCENT Type - (ACCENT Mode must be enabled).

   • ACCENT Type = OFF. The TRIGGER outputs are paired together with the 1st TRIGGER output responding to its assigned MIDI Note/Channel as normal, The 2nd TRIGGER output will only 'trigger' when the MIDI Velocity value is greater than 100. The pairings are (1 & 2), (3 & 4), (5 & 6) and (7 & 8).
   • ACCENT Type = ON. Only [TRIGGER 8] acts as an ACCENT output and will be fired if any of the other TRIGGER Outputs pass the ACCENT-LEVEL which is currently fixed at a MIDI Velocity of 100

The 8x LED’s indicate the status of each of the output triggers during normal operation and are also used during LEARN MODE to assist the user whilst programming the board.

The width of the TRIGGER pulse and the TRIGGER-lo and TRIGGER-hi voltages are set by onboard trimmers (see Calibration Guide for instructions)

LEARN MODE

LEAN MODE lets you assign different notes and channels to each TRIGGER. You could, for example, have four triggers on channel 10, two more on channel 11, one on channel 15 and one on channel 2.

To enter the LEARN MODE, hold down the LEARN button until all the LED’s come on and then release before the LED cycle pattern completes. The LED for the first channel to be set will flash once every second, indicating that it is waiting for a note to be assigned to trigger it. Once received it will trigger its output, and then flash the next LED showing it is waiting for the next trigger assignment.

If ACCENT MODE has been enabled and ACCENT TYPE is disabled, then you can only program the odd TRIGGER channels (1, 3, 5 & 7) and you will only need to program 4x MIDI Note/Channel combinations.

Repeat for all remaining triggers, if you don't want to reprogram all the outputs then simply wait, the unit will time out after roughly 4 seconds, saving any changes to trigger notes in flash memory.

The assignment of MIDI Channel and MIDI Note for the TRIGGERS can also be done using a MIDI SYSEX message.

NB: When assigning MIDI Channel and MIDI Notes the ACCENT assignments need not be the same as their associated TRIGGER output. This means you can switch between Standard and Accent modes and have 8 different assignments while in the Standard mode.

MIDI Trigger Assignments

The Factory Default TRIGGER assignments are:-

The status of the Trigger Assignments is indicated each time the module is powered up and after various events occur during normal operation:-

If in the Factory Default mode the LEDs will cycle from LED 1 through to LED 8 and back again
If in User Assigned mode the LEDs will cycle from the centre (LED4 and LED 5) to the ends (LED1 and LED 8) and back again

Assign Factory Defaults

To reset the MIDI Note and MIDI Channel assignments to the above factory defaults, press and hold the LEARN button, continue holding while the MIDI-Retrofit-8 cycles through an LED pattern, the unit should now automatically load the factory defaults.

Programming LEARN via MIDI

From V4.3 onwards it is now possible to define the MIDI Channel and MIDI Note values for the TRIGGERS using a SYSEX message:-

1) Set Channel/Note

Send -

F0 00 20 69 02 00 1c 1n 2c 2n 3c 3n … 7c 7n 8c 8n F7 (31 bytes)

where:- xc = MIDI Channel for TRIGGER x (values = 0 to 7 in hexadecimal)

xn = MIDI Note for TRIGGER x (values = 0 to 127 in hexadecimal)

Data for all 8 TRIGGERS must be sent with each having 3 bytes of data (c/n)

2) Request Channel/Note

Send -

F0 00 20 69 02 01 F7 (7 bytes)

Response -

F0 00 20 69 02 11 1c 1n 2c 2n 3c 3n … 7c 7n 8c 8n F7 (31 bytes)

where:- xc = MIDI Channel for TRIGGER x (values = 0 to 7 in hexadecimal)

xn = MIDI Note for TRIGGER x (values = 0 to 127 in hexadecimal)

Data for all 8 TRIGGERS will be received with each having 3 bytes of data (c/n)