Re: Sysex problems!
Re: Sysex problems!
- Subject: Re: Sysex problems!
- From: James Chandler Jr <email@hidden>
- Date: Fri, 4 Jul 2003 11:35:08 -0700
Hi Peter
If you parse out invalid messages, it ought to strip the garbage.
I have a MTPII interface on a G4Port serial card, but am just now
getting to the point of coding CoreMIDI, so can't comment yet on how
well the Griffin OSX serial MIDI driver works in practice. It was very
nice for Griffin to write the driver.
Here's one thing that could possibly go wrong with a multi-port MIDI
interface + serial driver--
The MIDI Time Piece appropriated an "unused" MIDI status byte, 0xF5, to
send/receive a two-byte-length CableSelect message. The
"CableSelectID" was merged with the MIDI Receive stream to identify
what MIDI Input connector the input messages come from. Similarly 0xF5
was interleaved on the Transmit stream to select the destination MIDI
Output connector.
This non-standard two byte message was 0xF5 + CableSelectID, with
CableSelectID typically in the range of 0 to 8 for a single 8 port
interface, and 0 to 16 for dual 8 port interfaces. CableSelectID 0 was
used if you wanted to transmit identical data to all output connectors.
Sorry to bore with useless trivia, but the non-spec message length of
2, could be a source of confusion for a serial driver, if the driver
doesn't know that 0xF5 messages are, in this case, two bytes long?
Perhaps a confused driver could turn CableSelectID messages into
occasional garbage?
James Chandler Jr.
On Thursday, July 3, 2003, at 11:12 PM, Peter Karlsson wrote:
Hi Doug and Kurt!
I have just tested MIDI Echo and I got exactly the same garbage
result. Look at this.
F0 41 37 00 23 30 01 00 00 00 00 00 01 01 07 04 01 00 02 00 00 0F 07
00 00 00 0C 00 00 00 00 0F 00 08 02 05 02 02 03 02 01 02 03 07 02 0D
02 01 02 05 03 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 01 01 00 00 01 01 07 04 01 00 02 00 00 0F 07
00 00 00 0C 00 00 00 00 09
00 0A 01 03 03 03 03 06 00 0E 02 02 02 0D 02 0A 01 0B 02 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 01 02 00 00 01 01 07 04 01 00 02 00 00 0F
07 00 00 00 0C 00 00 00 00 07 01 02 03 05 02 08 02 09 02 01 02 08 02
07 02 0E 01 0E 03 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 01 03 00 00 01 01 07 04 01 00 02
00 00 0F 07 00 00 00 0C 00 00 00 00 0B 00 08 02 00 03 0E 03 02 01 0D
02 0B 02 02 02 07 02 00 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 01 F7 00 00 00 00 00 00 00 01 F7 F7 F0 41 37 00
23 30 01 00 04 04 00 00 and so on...
I understand that I must use parsing but, this problem must be
corrected first!
Can it be my driver?
_______________________________________________
coreaudio-api mailing list | email@hidden
Help/Unsubscribe/Archives:
http://www.lists.apple.com/mailman/listinfo/coreaudio-api
Do not post admin requests to the list. They will be ignored.