what is my problem (midi question)...

[content]

Programming Logic to work with my evolver. set a sysex fader to what i think is right. when I scroll with the fader, the evolver goes to 15 then goes back down to 0. then it will go to 15 and back down to 0.

[Spandex]

sounds like it's only getting the first 4 bits. do you have an msb/lsb problem?

You're using sysex rather than straight midi controllers so are you packing two bytes in order to get better resolution? NRPNs?

[content]

it is nrpn's and in the string i have it set to LSB/MSB and have it set to the right bytes to change. I have done this before with logic and it worked fine.

[Spandex]

stabbing in the dark somewhat... I dunno logic or the evolver.. but a brief scan of the evolver midi spec suggests it's not NRPNs at all... rather it uses two nibbles in consecutive bytes (giving 0-255 rather than the NRPN range of up to about 16k).. with LS before MS. The 4-bit nibble thing would fit with your 0-15 problem... e.g.

Status Description
-----------------------
1111 0000 System Exclusive (SysEx)
0000 0001 DSI ID
0010 0000 Evolver ID
0000 0001 File Version
0000 0001 Program Parameter
0vvv vvvv Parameter Number 0 – 127.
0000 vvvv Parameter value, LS Nibble
0000 vvvv Parameter value, MS Nibble
1111 0111 End of Exclusive (EOX)

[content]

sorry, i am not real sure of the lingo, but that is how i have the fader set up. with the nibbles.

[Spandex]

Basically your most significant nibble isn't working.

I'm not sure if you already understand this.. but here's my boring explanation anyway... the single byte is being split across two bytes.. as the least significant end of both of them. So you multiply the MSN by 16 and add it to the LSN (which will always be 0-15). After the LSN wraps at 15, the MSN is incremented.. so u get 0-15.. then 16-31.. then 32-47 etc. The fact that you always get 0-15 shows your MSN isn't working for some reason.

This is either because you're sending both nibbles as a single full byte (i.e. without the zero padding) or because of "something else" I'm not sure if that's a very common setup (the split nibble thing, I don't remember seeing it before on the kit I've done sysex with, mostly Yamaha) so dunno if Logic won't need some coaxing to do it?? Normal NRPNs are actually two lots of 7-bits stuck together, giving a much larger range, and you shouldn't expect an "NRPN" setting to cut it here.

So.. having NO idea of how you go about these things in logic.. the general algorithm for this is to take your target value (a fader going from 0-255) and divide it by 16 to get your MSN and use the modulus for the LSN. Then you've got to pack them both into the right sysex packet as described in the spec.

The final thing to worry about is that evolver params aren't all mapped to the same 0-255 range.. some seem to be 0-160.. etc. I dunno how it behaves outside these legal ranges.. e.g. it might ignore, or it might wrap, or it go wonk.

Some sort of raw MIDI monitor would be handy.. mebbe there's sommat in logic. There's MIDI-Ox on PC. I wouldn't know for OSX.

Is this any use at all? Am I talking gibberish you don't understand? Or patronisingly explaining things that you do?

[content]

yeah it does make sense. I do kind of know this stuff but I appreciate the help. The frustrating thing is that I had it working before. Logic is usually real easy to program sysex faders. i have to look at it when i get home from work.