GEM SK760 Owner's Manual page 294

EXAMPLES OF EXCLUSIVE MESSAGES AND CHECKSUM CALCULATIONS
(relating to the structure of the Address Data Interface)
< Example 1 > : The setting for the 1st Effect Type of Group A on Hall 3 using the common channel 7, the format 0 (7 bit data value) and without
checksum.
According to the address map relating to the Performance Parameters -EFFECTS A the address is 00 13 00H (effctnr1) and the value relating to
HALL3 is 02H; therefore the set streams is as follows:
F0 2F 36 01 00
(1) (2) (3) (4) (5)
(1)Exclusive Status
(2)manufacturer ID=GENERAL MUSIC
(3)Command ID(3=RealTime) + device ID (6=7° device ID)
(4)Set Subfunction
(5)Model ID (0=WK4)
(6)c=0(No checksum),f=0(7 bit data value)
(7)EOX
< Example 2 > : The setting for the Attack of track 11 to +13 using common channel 2 (N.B. the 1st channel is 0 ), format 0 (7 bit data value) and with
checksum.
According to the address map relating to Performance Parameters - T_SLIDER the address relating to track 11 (the first track is 0) is 0A 1C 00H
(Attack) and the value to set is 4DH; therefore the set stream is as follows:
F0 2F 31 01 00
(1) (2) (3) (4) (5)
(1)Exclusive Status
(2)manufacturer ID=GENERAL MUSIC
(3)Command ID(3=RealTime) + device ID (1=2° device ID)
(4)Set Subfunction
(5)Model ID (0=WK4)
(6)c=1(Yes checksum),f=0(7 bit data value)
(7)EOX
The checksum value is obtained with an XOR of all the bytes starting from the GeneralMusic ID (2FH) included; using ^ as the operator XOR ( OR
Exclusive ), then:
cc=checksum = 2F ^ 31 ^ 01 ^ 00 ^ 10 ^ 0A ^ 1C ^ 00 ^ 4D = 54
the message to send is:
F0 2F 31 01 00 10 0A 1C 00 4D 54 F7 .
< Example 3 > : Setting the M.Transpose to -6 using common channel 2, format 0 (7 bit data value) with and without checksum.
According to the address map relating to the Global Parameters - GLOBSET the address is 00 09 02H (transpose) and the value to set is 24-
6=18=12H; therefore the set stream without checksum is as follows:
F0 2F 31 01 00
(1) (2) (3) (4) (5)
(1)Exclusive Status
(2)manufacturer ID=GENERAL MUSIC
(3)Command ID(3=RealTime) + device ID (1=2° device ID)
(4)Set Subfunction
(5)Model ID (0=WK4)
(6)c=0( No checksum),f=0(7 bit data value)
(7)EOX
with the checksum, the stream will be:
F0 2F 31 01 00 10 00 09 02 12 16 F7 .
< Example 4 > : setting the parameter FltCutoff of the group AUDIOIN1 to 147 ( >127 ) on command channel 2 and format 2 ( data in nibble )
with and without checksum.
According to the address map relating to Global Parameters - AUDIOIN1 the address is 00 0B 05H (FltCutoff) and the value to set in nibble format
is, 09 03H; infact 147=93H, therefore the value is sliced in two nibbles 9 and 3 obtaining 09 03H; therefore the set stream without checksum is as
follows:
F0 2F 31 01 00
(1) (2) (3) (4) (5)
(1)Exclusive Status
○ ○ ○ ○ ○ ○ ○ ○ ○ ○
A•30 Appendix
00 00 13 00 02
(6) address data (7)
10 0A 1C 00 4D
(6) address data checksum (7)
00 00 09 02 12
(6) address data (7)
02 00 0B 05 09 03 F7
(6) address data (7)
○ ○ ○ ○ ○ ○ ○ ○ ○ ○
F7
cc=?? F7
F7
○ ○