SHX8 jitter

Testing/Troubleshooting
1

Hi

I just read the other “jitter” post, and I probably should check on my soldering again, though right now I would like to avoid this because

  1. all my modules work fine for themself AND

  2. all my modules are installed and wired up. (64 AIN and 64 AOUT)

here is my problem:

I run midibox64 with 64 AIN’s connected to pots and 64 AOUT connect to a PWM-module I reengineered and adapted.

with the pwm I am able to dimm 64 12V lamps. this works fine, though my PWM works only between 4V and 7V, so  I cannot use the whole midi range of 127 values but only a range of 30. but this is enough for my purpose. this works fine.

the problem starts when a value change occours on a AIN pot (for example CC 91 Ch 5). this sets the voltage of the AOUT pin (in this example CC 91 Ch 5) on the voltage corresponding to the value sent by the AIN, until I send a midi signal to this pin  (again CC 91 Ch 5)  and it changes back to the sent value.

this means for my lamp it either just switches off (above 7V) or on (below 4V) or it simply flickers if its in the process of dimming.

since its an  AIN pot that influences only the corresponding AOUT pin I assume its rather an application issue than a wiring or soldering problem.

ah yes: I disabled midi merge.

any suggestions highly appreciated.

cheers

martin

2

got it sorted:

TK helped me with a code snippled for the midbox64 app:

inside mb64_pots.inc:

MB64_POT_Handler

        ;; save current pot number in MB64_CURRENT_POT

        SET_BSR MB64_BASE

        movwf  MB64_CURRENT_POT, BANKED

movlw 0xb0

call MIOS_MIDI_TxBufferPut

movff MB64_CURRENT_POT, WREG

call MIOS_MIDI_TxBufferPut

movf MIOS_PARAMETER2, W

goto MIOS_MIDI_TxBufferPut

this stops the internal  communication between the AIN’s and AOUTs and reduces the comunication on pure midi.

thanks again Thorsten

cheers

martin