[iiwusynth-devel] Bank select through MIDI

[James Hightower]

Hi all,

I've just started working with iiwusynth, as a soft synth for Rosegarden.
I noticed that it is impossible to select bank 128 through a MIDI bank
select.
The problem is at iiwu_chan.c line 206 (in the CVS version):

  iiwu_channel_set_banknum(chan, (((unsigned int) value & 0x7f)
               + ((unsigned int) chan->bank_msb << 8)));

(it's line 168 in the release version)

The problem is that the MSB and LSB are being treated as 8 bit bytes,
which they are not. They are 7-bit bytes, so the MSB should be shifted 7
bits to the left. This allows for 2^14 or 16384 banks, 0-16383, which is
correct as per the MIDI standard. Shifting by 8 bits allows banks 0-32639
but skipping banks 128-255, as bit 7 of the LSB cannot be set, which is
not correct.
Looking through the mailing list archives, I see that Josh touched on this
subject in an email dated Sat Apr 06 15:20:07 2002, in a discussion of
someone's keyboard, and this was also brought up by
address@hidden in an email dated Jul 12 22:31:59 2002, but there
was no further discussion.
Here's a patch -- I havn't tested this beyond running this with
Rosegarten, and I really havn't looked at the code closely....

iiwu_chan.c.patch
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