GEMS modulation bug?

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SeregaZ
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Posts: 17
Joined: Mon Aug 03, 2015 12:45 pm

GEMS modulation bug?

Post by SeregaZ » Fri Jun 28, 2019 12:07 pm

for create some bend, slides - GEMS have modulation. it is instructions, where says how frequency of note need to be changed in a time.
it have:
2 bytes - starting pitch
[segment]
1 byte - counter
2 bytes - speed
[segment]
1 byte - 0 - end of modulation.

GEMS software for modulation editor shows it can be 20 segments. then increase button is not work. so i think it is limit 20. but practice says modulation is hung up after 10 segments.

it is GEMS's bug? who knows - can it be fixed? for 20 "official" segments, or even bigger value - for 127 for example.


* if by some miracle some GEMS's specialist will come into this topic:
1. how to increase instruments and modulations? original GEMS's banks have limit for 127 instruments and 127 modulations. can that ".byte" changed to ".write" type of variable? i mean from 1byte's 127 limit to 2bytes 32k?
2. when modulation is end - it reset frequency of note to starting note's frequency. can it be changed too? i mean when modulation is end - just left that frequency, that is reach after end of modulation and hold it, until note is stop playing.
3. can it be adding some additional command for tracks - stereo switcher and AMS FMS? that params is lays inside instrument. if you want to change paning - it need to clone instrument, change flag of paning and use, that is increase used instruments. some another drivers have some internal command for switch paning. can it be applyed to GEMS too?

SeregaZ
Interested
Posts: 17
Joined: Mon Aug 03, 2015 12:45 pm

Re: GEMS modulation bug?

Post by SeregaZ » Thu Nov 19, 2020 9:13 pm

oh, i didnt add that info, what i found later about that bug :)

GEMS have modulation buffer. some kind of... 128 bytes probably. and it split between 4 modulation - per 32 bytes for one. it no have rewrite options. i mean when over 10 iterations happen - need to write what is left of that modulation by back to starting place, but it just hung. so that modulation is limited to 10 steps. and it means you cant use more, than 4 modulations at once. if you remember GEMS can have a lot of tracks - 16, but only 4 of them can have modulations, that plays same time.

when i made converter from Deflemask to GEMS - that bug is broke my head :) so i am create some cheks for count how many steps for modulations is and create modulation, if less than 10. if bigger - recreate same modulation effect by pitch command. it eat much more space, but ok. but my opinion - just do not make songs with that modulations effects in Deflemask :))) so create modulation itself - no problem. problem to make some formula, to correct count that modulation, i mean transfer Deflemask's modulations (01, 02, 03, E1, E1 effects) into GEMS modulation. i am still have drunk cats as final result. but will be nice to solve this problem, but probably not at this universe...

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