Version 1.03; Version 1.04 - Alesis D4 Service Manual

9.30 Version 1.03

1/2/92
1 A bug existed in the v1.02 voice allocation routine that would cause short sounds or individual
samples within sounds to drop out or sputter until the machine was powered off. This is now fixed.
2 A bug existed (in v1.02 only) that could prevent the user from selecting a new trigger note number
for triggers 3, 7, and 11. This is now fixed.

9.40 Version 1.04

3/19/92
1 A bug existed (in v1.03 only) that could crash the machine if a flurry of notes were sent to the D4
and if some of the voices assigned to those notes were set to SINGLE, GROUP1, or GROUP2 mode. This
is now fixed.
2 The system exclusive receive routine has been modified so that the time out period used to detect
unplugged midi cables and unfinished system exclusive messages is now 250mS instead of 80mS as in
earlier versions. This was done to allow slow computers more time while transmitting to the D4 before
the D4 panics and aborts the sysex load. In addition, the LCD will now correctly display the "MIDI
BUFFER OVERFLOW" message when the buffer overflows during sysex reception instead of the
"SYSEX DATA ERROR" message.
3 The signal threshold for the diagnostics trigger self-test has been lowered even further to keep
units from failing unnecessarily in repair.
Alesis D4/D5 Drum Modules Service Manual 17 02/19/03