Roland M-GS64

Examples of actual MIDI messages
«Example I> 9236 SF
nis the Nofe-an stotus, ond n is the MIDI channel number, Since 2H = 2, SEH = 42, and SFH = 95, this iso Note-on
messnge with MIDI CH = 3, note number 62 (note name is D4), and velocity 95.
<Exmple 2> (E49
Galt is the Program Chonge status, ond n is the MID! chonnel number. Since FH = 14 and 49H = 73, this is
Program Change messge with MIDI CH = 15, program number 74 (Flute in GS}.
<Exomple 3> EA 00 28
Eni! is the Pitch Send Change status, and n is the MIDI channel number. The 2nd byte (00H=0} is the LSB ond the
‘3rd byte (28H=40) is the MSB, but Pitch Bend Value iso signed number in which 40 OOH { = 64 x 128 +0 = 8192}
js 0, so this Pitch Bend Value is
28 OOH - 40 GOH = Gx 128 +0-{64 x 128 +0} = 5120 - 8192 = -3072
If the Pitch Bend Sensitivity is set to 2 semitones, -8192 (00 OOH} will couse the piteh te change -200 cents, so in this
case -200 x (-3072) + (-8192) = -75 cents of Pitth Bend is being applied to MIDI channel 11.
Example 4> B3 64 00 65.00 06 OC 26 00 64 7F 65 7F
Bat is the Control Chonge stotus, ond n is the MIDE channel number. For Control Changes, the 2nd byte is the control
number, ond the 3rd byte is the volue. Ino cose in which two or more messages consecutive massages have the
some stolus, MIDI has @ provision called “cunning status” which allows the stotus byte of the second ond following
messages to be omitted, Thus, the above messages have the following meaning.
83 6400 MIDI ch.4, lower byte of RPN parameter number 2 00H
(B3} 65.00 (MIDE ch.4} upper byte of RPH parameter number 2 00H
{83} 060C (4I0b ch4) upper byte of value 0th
(83) 26.00 {MID} ch.4} fower dyie of value : 00H
(83) O47F {MIDI ch.4) lower byte of RPN porameter number TF
{B3} 6578 {MIDI ch.4} upper byte of RPN parameter aumber TH
In other words, the above messages specify o value of OC OOH for RPN porameter number 00 OOH en MID! channel
4, ond then set the RPN porumeter number to 7F 7FH.
RPH porameter number 09 OOH is Pitch Bend Sensitivity, and the MSB of the value indicates semitone units, so a
value of OCH = 12 sets the maximums pitch bend range to +- 2 semitones (t octave). (On G5 sound sources the LS8
of Pich Bend Sensitivity is ignored, but the USB should be transmitted anywoy (with o value of 0} so that ozerotion
will be correct on any device,
Once tha parcmater number has been specified for RPN or NRPH, cll Dota Entry messages tronsmitied on thar some
channel will be valid, so ofter the desired value has been transmitted, it is e good iden to set the parameter number
to 7F7FH to prevent accidents. This is the reason for the (23) 64 7F (B3) 65 PF of the end,
1 is not desirable for performance dota (sweh os Standard MIDI File data} to contoin mony events with running status
os given in cExomple 4>, This is becouse if ployhack is halted during the song ond then rewound of fost-forwarded,
the sequencer may not be able to transmit the correct status, and the sound source will then misinterpret the dota.
Take core to give each event its cwn stetus.
Ii is olsa necessary thot the RPM or NRPR porometer number setting ond the volue setting be done in the proper
order, On some sequencers, events accuting in the same (or consecutive) clack may be transmitted in on order differ-
ent than the order in which they were received. For this reason it is a goad ides fo slightly skew the time of each
event (about | tick for TPON=96, ond about 5 ticks for TPON=480).
"TPQN : Ticks Per Quarter Note
50
Example of an Exclusive message and calculating a Checksum
Rolund Exclusive messages (RQ1, DT} ure Ironsmitted with o checksum of the end {before F7] to make sure that the
message was correctly received, The value of the checksum is determined by the address und dato (or size} of the
ttansmitted exclusive massage.
* Hew fo cakulate the checksum imal numbers ore indicated by ’H’)
The checksum is 0 value derived by adding the address, size and checksum itself and inverting the fower 7 hits.
Here’s an example of how the checksum is cokulated, We will assume thot in the exclusive message we are tronsmit-
fing, the address is ou bb ccH ond the data or size is di ee HH.
aotbb+c+ddsees i=sum
sum + }2B = quotient ... remoinder
428 - remainder = checksum
<Example 1> Setting REVERB MACRO to ROOM 3
According to the “Parameter Address Map", the REVERB MACRO Address is 40 O1 30H, ond ROOM 3 is @ value of
02H. Thus,
fm 4 10 2 2 40.01 30 02 n fl
ay {2} (3) {4} {5) address date checksum — {6)
{1}Exclusive Status (2)10 {Rolend) {3)Device 1D (17}
{4\IModet 1D {65} (5)Command iD {DT1) (6)End of Exclusive
Next we calculate the checksum.
40H + O1H + 30H + 02H = 6441448 +2=11S{sum)
11S{sum) + 128 = O{quotient) ... 11 S{remaindar)
checksum = 128 - 1) S{remoinder) = 13 = ODH
This means thot FO 4} 10 42 12 40 07 30.02 0D £7 is the messoge we transmit.
Example 2> Requesting tronsmission of the LEVEL for DRUM MAP ] NOTE HUMBER 75 (D4; Cloves}
NOTE NUMBER 75(D#5) is 4BH in hexadecimal.
According to the “Porameter Address Map”, LEVEL of NOTE HUMBER 75 (D#5; Cloves) in DRUM MAP } hos an
Address of 41 02 48H ond a Size of 00 06 OTH, Thus,
fm Al 10 2 u 410248 goo0G! 7 7
MQ (3) {4} {5) address size checksum — {6}
(1)Excusive Stetus {210 {Rofand) {3)Device 10 (17)
{4)Model 1D (6S) (5}Commond 10 (ROT) {b}End of Exclusive
Next we colculnte the checksum,
AlH+ O2H + 4BH + OOH + 00H +O1H = 65+2+75+0+0+4 i= 143{sum)
}43{sum] + 128 = l{quotient ...
checksum = 128 - ! Stremainder
Tris means that £0 44 1042 11 41.02 4B 00 G6 01 71 F7 is the message we tronsmit,