Generalmusic GEM SK760 Instructivo De Instalacion Y Guia Del Usuario página 367

The transmission of one of the available resources starts by sending a message (File Header message) to indentify the successve
blocks of data desired (File Data message).
Typically the files concerned can be relatively long, therefore it is better to subdevide the information into several brief packets
which can be individually tested and eventually retransmitted (in the case of using the handshake mode and the reception of an
ACK reply confirms the correctness of the packet received, while a reply of the type NACK forces the retransmission of the error
packet).
Should it be necessar to interrupt the transmissoin, it is always possible to send the CANCEL command at any moment during the
course of the communication.
A WAIT command has also beed included for future implementations.
File Header message:
F0H = System Exclusive Message status
2FH = ID number (manufacturer ID) = GENERAL MUSIC
5cH = Command ID: 5=Resource Access, c=device ID(0-F)
01H = Subfunction ID = FILE HEADER
00 = Model ID, 00 = WK4
03H = not checksum, format 3 (octect)
<data> = 3 octects
F7H = EOX
File Data message:
F0H = System Exclusive Message status
2FH = ID number (manufacturer ID) = GENERAL MUSIC
5cH = Command ID: 5=Resource Access, c=device ID(0-F)
02H = Subfunction ID = FILE DATA
00 = Model ID, 00 = WK4
13H = checksum, format 3 (octect)
pp = packet number (00:7fH)
<data> = 15 octects
cc = checksum
F7H = EOX
Resource Request message:
F0H = System Exclusive Message status
2FH = Manufacturer ID = GENERAL MUSIC
5cH = Command ID: 5=Resource Access, c=device ID(0-F)
03H = Subfunction ID = RESOURCE REQUEST
00 = Model ID, 00 = WK4
00 = not checksum, format 0
tt = Resourse ID
ss = all files(0), selected(>0)
F7H = EOX
Resource ID:
8
9
SETUP di sistema
SOUNDS
REAL PERFORMANCES
STYLE PERFORMANCES
USER STYLES
SONGS
ACK
NACK
CANCEL
WAIT
0
1
2
3
4
5
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System Exclusive A•37
7FH
7EH
7DH
7CH
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