D4 Software History; Version 1.01; Version 1.02 - Alesis D4 Service Manual

9.00 D4 Software History

9.10 Version 1.01

9/15/91
First production release. Changed the offensive drumset names found in version 1.00.

9.20 Version 1.02

12/13/91
1 A triggering bug existed when using two or more drum pads that would cause a pad hit to be
ignored when a neighboring pad had been struck hard immediately before it. This would usually occur on
the second hit of a two pad flam, or on the first hit to a tom pad during a drum-roll on the snare.
2 The trigger TYPE parameter has been replaced with three new parameters. These are the cross-
talk suppression parameter XTALK, the post-trigger decay/recovery time parameter DCAY, and the noise
floor threshold parameter NOISE. To accommodate these new parameters, a new page has been added
under the EXT TRIG functions.
3 The trigger inputs now have an adjustable VCURVE parameter on the first page under EXT TRIG.
(Where TYPE was.) This parameter selects one of seven pad-force to midi velocity response curves to
suit different playing techniques.
4 The diagnostics routine's ram test is now non-destructive.
5 The signal threshold for the diagnostics trigger self-test has been lowered to keep units from
failing unnecessarily in repair.
6 The note number assignment of trigger 9 has been changed on most preset drumsets from 039 D#1
(handclap) to 057 A2 (crash cymbal 2).
7 The dynamic voice allocation scheme has been improved so that voice-stealing is less noticeable.
8 Any system exclusive messages received that included nested midi real-time messages (i.e. timing
clocks, active sensing, start, stop, or continue) would cause the system exclusive data to be ignored and
the SYSEX DATA ERROR message would be displayed. This has been fixed so that any nested real-
time message are ignored, and the sysex data reception continues uninterrupted.
9 A new system exclusive message has been added (opcode 05H) to transmit and receive the new
trigger parameters. The new sysex messages will allow version 1.01 software to upload trigger gains to
version 1.02, but the trigger types will be ignored. Version 1.02 trigger parameters sent to a version 1.01
machine will be ignored completely.
10 The reception of a "System Info Request" system exclusive message (opcode 40H) would result in
the transmission of the complete 25 packet system exclusive dump of the entire D4's memory. This has
been changed so that only the System Info message packet is sent.
11 The system exclusive message that allows an external device to display characters on the LCD
(opcode 04H) had a bug that would cause the SYSEX DATA ERROR message to be displayed instead.
This now works properly.
Alesis D4/D5 Drum Modules Service Manual 16 02/19/03