Request Data1 RQ1 11H | Roland GR-20 specification

Chapitre 6 Appendices

●Request Data1 RQ1 (11H)

THis message is to request the GR-20 to transmit its parameters.

The address and size indicate the type and amount of parameters requested. The GR-20 itself does not send this message.

When the GR-20 receives this message, it responds with appropriate parameters if the following conditions are satisfied:

1.The address indicated with RQ1 matches with one of the parameter base address of the GR-20

2.When the Bulk Load standby mode.

With these conditions provided, the GR-20 transmits specified parameters in Data Set 1 (DT1) message.

Byte	Comments
F0H	System Exclusive Status
41H	Manufacturer ID (Roland)
10H	Device ID (Dev=10H)
00H	Model ID MSB (GR-20)
72H	Model ID LSB (GR-20)
11H	Command ID (RQ1)
aaH	Address MSB
bbH	Address
ccH	Address
ddH	Address LSB
ssH	Size MSB
ssH	Size
ssH	Size
ssH	Size LSB
sum	Check sum
F7H	EOX (End Of Exclusive)

●Data Set 1: DT1 (12H)

The GR-20 transmits this message in the following conditions.

If the address matches with one of the parameter base addresses of the GR-20, the received data is stored at the specified address of the memory.

The GR-20 transmits this message in the following conditions.

When data request (RQ1) is received with the Bulk Load mode, and the specified parameters are transmitted.

or you executes Bulk Dump function.

Regarding details of the parameter transmitted/sended, please refer to the Parameter Address Map.

Byte	Comments
F0H	System Exclusive Status
41H	Manufacturer ID (Roland)
10H	Device ID (Dev=10H)
00H	Model ID MSB (GR-20)
72H	Model ID LSB (GR-20)
12H	Command ID (DT1)
aaH	Address MSB
bbH	Address
ccH	Address
ddH	Address LSB
eeH	Data
:	:
ffH	Data
sum	Check Sum
F7H	EOX (End of Exclusive)
Model ID	The Model ID of the GR-20 is 00H 30H.
Device ID	Device ID of the GR-20 is fixed at 10H.

/Example of creating the exclusive message/

If you want to set as the following the parameter LEVEL/FREQ/RESO TRANSPOSE of USER BANK 01 Patch, create data as the following and send it to your GR-20.

Reverb setting:

LEVEL: 90

FREQ: 50

RESO: 60

TRANSPOSE: +1oct

Tramsmitted data:
F0H 41H		10H 00H 72H 12H 01H 00H 00H 06H 5AH 32H 3CH 03H 2EH F7H
1	2	3	4	5	6	7	8	9

1.Exclusive status is F0H.

2.Roland’s Manufacturer ID is 41H.

3.This is the device ID.(Fixed at 10H for GR-20)

4.Model ID of the GR-20 is 00H 72H.

5.DT1(Data Set1) Command ID is 12H.

6.These are the parameter addresses. Please find the start address of the USER BANK 01 Patch from the table of the start address.You can find the address as 01H 00H 00H 00H. Next, please find the offset address of the LEVEL Parameter from the table 4-2. That is 00H 00H 06H.The result will be 01H 00H 00H 06H.

	01H 00H	00H 00H	(the start address of the USER patch)
+)	00H	00H 06H	(the offset address of the LEVEL)
----------------------------
	01H 00H	00H 06H

7.The settings value for LEVEL is 90. This is expressed as 5AH in hexadecimal notation with two digits. (Refer to the attached Chart A-1)

The settings value for FREQ is 115. This is expressed as 32H in hexadecimal notation with two digits.

The settings value for RESO is 60. This is expressed as 3CH in hexadecimal notation with two digits.

The settings value for TRANSPOSE is +1oct. This is expressed as 03H in hexadecimal notation with two digits from Table 4-4.

8.This is the check sum byte.The error checking process uses a Checksum and provides a pattern where the last significant 7 bits are zero when values for address, data(or size) and the Checksum are summed.

If the address of the exclusive message that you wish to send is aa bb cc ddH and the data(or size) is ee ff hh iiH,

aa+ bb + cc + dd + ee + ff + hh + ii = sum sum / 128 = quotient ...remainder

128 - remainder = checksum

* However, when sum=0, then the checksum also results in 0.

In case of this example,

F0H 41H 10H 00H 72H 12H 01H 00H 00H 06H 5AH 32H 3CH 03H ??H F7H

address

data

checksum

Using the above formula, Checksum will be as follows.

01H + 00H + 00H + 06H + 5AH + 32H + 3CH + 03H = 1 + 0 + 0 + 6 + 90 + 50 + 60 + 3 = 210(sum)

210(sum) / 128 = 1(quotient) ...82(remainder) checksum = 128 - 82(remainder) = 46 = 2EH

If you calculate with hexadecimal,

aa+ bb + cc + dd + ee + ff = sum(xxH) sum(xxH) / 80H = quotient ...remainder 80H - remainder = checksum

Checksum will be as follows.

01H + 00H + 00H + 06H + 5AH + 32H + 3CH + 03H = D2H D2H / 80H = 01H(quotient) ...52H(remainder) checksum = 80H - 52H(remainder) = 2EH

9. F7H is the mark of the end of exclusive.