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  Monday, 06 June 2022
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Is it possible to create a sysex message for expression from a hexidecimal string as pictured? This picture was received from the Roland fc300 expression pedal.https://share.icloud.com/photos/096qVN3m2TbIRPok18Z2OAYzQ
2 months ago
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#14788
0
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Undo
OK, I've managed to get at your picture.

The data I see there is a stream of midi. Quite a few timing bytes, with some actual midi in the middle. Some Controller data for Channel 1, then some for Ch 4, maybe a little more lower down.

This is all plain, standard, MIDI. Not SysEx. You could make a little midi file with this in, and 'play' it whenever, and send it through. SysEx would need a LOT of extra info, and the data might need to be somewhat different, so it would be a LOT of extra work, if it was possible. Why bother if you can just send the MIDI?

To give you the full data, what's there is the block for Ch 1 controller (the lines starting B0). Two lines for RPN LSB and then MSB, followed by Data Entry (2 bytes) then two bytes of data? Then looks like tqo more RPN lines for end of instruction.

Then something very similar (exactly the same ?) for B3 (Channel 4).

Was there some reason why you were thinking SysEx, rather than just a little midi file? Do you have some way to 'play' a midi file of instructions - i.e. no actual music?

Geoff
2 months ago
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#14789
1
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Roland FR4x accordion needs sysex for a pedal control. It is found on page 80 foot pedal parameters setup on the Roland. I have managed to create the sysex to control function 1-9, but would it be possible to create a sysex to control expression. See fc300 manual page 64…I managed to create the sysex for push buttons 1-9 as in picture link. But not quite familiar with how expression would work in this application. Thinking of using the Morningstar pedal which capable of sending sysex and an expression pedal can be also programmed…

See page 80
https://static.roland.com/assets/media/pdf/FR-4x_reference_e01_W.pdf

See page 64
https://static.roland.com/assets/media/pdf/FC-300_OM.pdf#page64

Sysex for pushbuttons…
https://share.icloud.com/photos/0828FWBryvxjpcCUdvbjvZDgA
2 months ago
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#14790
0
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Undo
Situation: You want to send the same format of System Exclusive messages that the Roland FC-300 foot controller sends so that you can control the Roland FR-4x accordion. You have already determined the System Exclusive messages that the foot switches send. Now you are trying to determine the System Exclusive messages the expression pedals send.


Note: There are two expression pedals on the Roland FC-300. Each expression pedal has a dual function:
  • You can tilt the pedal between heel down and toe down to control the value of some effect.
  • If you press firmly on the toe end of the pedal, you can toggle an effect off or on.

The FC-300 manual describes the System Exclusive messages that it sends starting on page 64. Based on the manual and your notes, the System Exclusive messages use the following pattern:
F0 41 10 00 00 20 12  w  x  y  z F7

w Address Big
x Address Small
y Data
z Checksum

Here are the messages for the expression pedals:
                               F0 41 10 00 00 20 12  w  x  y  z F7

Expression Pedal 1 tilt min F0 41 10 00 00 20 12 24 00 00 5C F7
Expression Pedal 1 tilt max F0 41 10 00 00 20 12 24 00 7F 5D F7
Expression Pedal 2 tilt min F0 41 10 00 00 20 12 24 01 00 5B F7
Expression Pedal 2 tilt max F0 41 10 00 00 20 12 24 01 7F 5C F7

Expression Pedal 1 toggle off F0 41 10 00 00 20 12 22 00 00 5E F7
Expression Pedal 1 toggle on F0 41 10 00 00 20 12 22 00 7F 5F F7
Expression Pedal 2 toggle off F0 41 10 00 00 20 12 22 01 00 5D F7
Expression Pedal 2 toggle on F0 41 10 00 00 20 12 22 01 7F 5E F7

In the tilt messages, the data value (y) can be between hex 00 and 7F (decimal 0 and 127).

To generate the correct checksum (z), follow these steps:

A. In decimal, find the sum of w + x + y.
B. Find the reminder of A divided by 128.
C. Calculate 128 - B.

Use the result from step C in hex as the checksum.
2 months ago
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#14791
0
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Undo
Thanks for this…give you my results soon…
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