Emu XL-7 & MP-7 User's Group

Its very strange. I am also seeing the values change depending on 
manual adjustments in the front panel. But when I come to actually 
trying to calculate from scratch, I never get the same value as they 
do. I have tried every combination of the first 6 bytes (the header), 
both with and without including the name, either XORing or ADDing and 
trying additional subtraction from 0x80 or XORing the result with 
0x7f. So I went back to my standard routine and tested it on a non-
Emu module and it worked fine. In then end I found that if I set the 
checksum to 0x7f it works. It shouldn't, but it does. I think it's a 
bug.

As for the Single Note Change, it is doing nothing for me. I would 
expect to be able to send it and get an immediate effect when I play 
the note (I don't). If I send a whole table, it works fine.
Keith

--- In xl7@yahoogroups.com, "steve_the_composer" <smw-mail@...> wrote:
>
> Just did a quick test as follows [on XL-2500]:
> 
> (1) On C-2 of USer Table 1 I changed coarse to 127 and fine to 63.
> (2) I requested table 1: f0 7e 00 08 00 00 f7
> 
> Here's the first part of the dump:
> 
> F0 7E 00 08 01 00 [header]
> 55 73 65 72 20 54 75 6E 69 6E 67 20 30 30 30 20 [name]
> 7F 7E 00 [C-2]
> 01 00 00 [C#-2]
> 
> (3) I then changed C-2 back to its original
> 00 00 00
> 
> (4) Since I added 03, I subtracted 03 from the check sum.
> 37 became 34
> 
> (5) I then sent the dump back and since I had the table up
>  on display, I saw the 127 and 63 change back to 000 and 00.
> 
> I imagine the other P2Ks should work the same way.
> 
> BTW, I seem to recall on the P2K message board a few of us 
discussed 
> tuning systems. This was a year or two ago.
> 
> I will check out the single note change.
> 
> --Steve
> 
> PS: My checksum calculation (Roland gear) was either for the 
> Commodore 64 or the Intel 8086/8088 and may have been in assembly 
> lang. I would have used an 8 bit variable, shifted left, then right 
> to drop the 8th bit and finally subtracted from 80h. If I ever find 
> the code, I will check to see if I used the XOR.
>