Roland MMP-2 Appendices, Example of system exclusive message and, Checksum calculation

MIDI Implementation

48H	—	400	58H	—	1000	68H	—	2500	78H	—	6300
49H	—	422	59H	—	1060	69H		2660	79H	—	6700
4AH —		450	5AH —		1120	6AH —		2800	7AH —		7100
4BH —		473	5BH —		1200	6BH —		3000	7BH —		7500
4CH —		500	5CH —		1250	6CH —		3150	7CH —		8000
4DH —		530	5DH —		1330	6DH —		3350	7DH —		——
4EH —		560	5EH —		1400	6EH —		3550	7EH —		——
4FH —		600	5FH —		1500	6FH —		3760	7FH —		——

+——————————————————————————————————————————————————————————————————————————+ MIDI Data - PREAMP Type Table

+————————+————————+
	Data		TYPE
+————————+————————+
	00H		RED7
	01H	-	N1073
	02H	-	MANSS
	03H	- AVTUBE
	04H	- AVSOLS
	05H	- HHTUBE
	06H	- MILLHV
	07H	- SATUBE
	08H	- CSSLST
+————————+————————+

MIDI Data - PREAMP Gain Table

+————————+————————++————————+————————++————————+————————++————————+————————+ Data Gain(dB) Data Gain(dB) Data Gain(dB) Data Gain(dB) +————————+————————++————————+————————++————————+————————++————————+————————+

		20H		— 3.2	40H		0.0	60H		3.2
		21H		— 3.1	41H	—	0.1	61H	—	3.3
		22H	—	— 3.0	42H	—	0.2	62H	—	3.4
		23H	—	— 2.9	43H	—	0.3	63H	—	3.5
04H	6.0	24H	—	— 2.8	44H	—	0.4	64H	—	3.6
05H	5.9	25H	—	— 2.7	45H	—	0.5	65H	—	3.7
06H	5.8	26H	—	— 2.6	46H	—	0.6	66H	—	3.8
07H	5.7	27H	—	— 2.5	47H	—	0.7	67H	—	3.9
08H	5.6	28H	—	— 2.4	48H	—	0.8	68H	—	4.0
09H	5.5	29H	—	— 2.3	49H	—	0.9	69H	—	4.1
0AH	5.4	2AH —		— 2.2	4AH —		1.0	6AH —		4.2
0BH	5.3	2BH —		— 2.1	4BH —		1.1	6BH —		4.3
0CH	5.2	2CH —		— 2.0	4CH —		1.2	6CH —		4.4
0DH	5.1	2DH —		— 1.9	4DH —		1.3	6DH —		4.5
0EH	— 5.0	2EH —		— 1.8	4EH —		1.4	6EH —		4.6
0FH	— 4.9	2FH —		— 1.7	4FH —		1.5	6FH —		4.7
10H	— 4.8	30H	—	— 1.6	50H	—	1.6	70H	—	4.8
11H	— 4.7	31H	—	— 1.5	51H	—	1.7	71H	—	4.9
12H	— 4.6	32H	—	— 1.4	52H	—	1.8	72H	—	5.0
13H	— 4.5	33H	—	— 1.3	53H	—	1.9	73H	—	5.1
14H	— 4.4	34H	—	— 1.2	54H	—	2.0	74H	—	5.2
15H	— 4.3	35H	—	— 1.1	55H	—	2.1	75H	—	5.3
16H	— 4.2	36H	—	— 1.0	56H	—	2.2	76H	—	5.4
17H	— 4.1	37H	—	— 0.9	57H	—	2.3	77H	—	5.5
18H	— 4.0	38H	—	— 0.8	58H	—	2.4	78H	—	5.6
19H	— 3.9	39H	—	— 0.7	59H	—	2.5	79H	—	5.7
1AH	— 3.8	3AH —		— 0.6	5AH —		2.6	7AH —		5.8
1BH	— 3.7	3BH —		— 0.5	5BH —		2.7	7BH —		5.9
1CH	— 3.6	3CH —		— 0.4	5CH —		2.8	7CH —		6.0
1DH	— 3.5	3DH —		— 0.3	5DH —		2.9
1EH	— 3.4	3EH —		— 0.2	5EH —		3.0
1FH	— 3.3	3FH —		— 0.1	5FH —		3.1

+————————+————————++————————+————————++————————+————————++————————+————————+

Appendices

precision is required, we must use two or more bytes. For example, two hexadecimal numbers aa bbH expressing two 7-bit bytes would indicate a value of aa x 128 + bb.

*In the case of values which have a ± sign, 00H = -64, 40H = ±0, and 7FH

=+63, so that the decimal expression would be 64 less than the value given in the above chart. In the case of two types, 00 00H = -8192, 40 00H = ±0, and 7F 7FH = +8191.

*Data marked “nibbled” is expressed in hexadecimal in 4-bit units. A value expressed as a 2-byte nibble 0a 0bH has the value of a x 16 + b.

<Ex.1> What is 5AH in decimal system? 5AH = 90 according to the above table.

<Ex.2>What in decimal system is 12034H in hexadecimal of every 7 bit? 12H = 18, 34H = 52 according to the above table. So 18 x 128 + 52 = 2356.

<Ex.3> What in decimal system is 0A 03 09 0D in nibble system? 0AH = 10, 03H = 3, 09H = 9, 0DH = 13 according to the table.

So ((10 x 16 + 3) x 16 + 9) x 16 + 13 = 41885.

<Ex. 4> What in nibble system is 1258 in decimal system?

____

16)1258

16)78 ... 10

16)4 ... 14

0 ... 4

0 = 00H, 4 = 04H, 14 = 0EH, 10 = 0AH According to the table. So it is 00 04 0E 0AH.

●Example of system exclusive message and

Checksum calculation

On Roland system exclusive message (DT1), checksum is added at the end of transmitted data (in front of F7) to check the message is received correctly. Value of checksum is defined by address and data (or size) of the system exclusive message to be transmitted.

●Decimal and Hexadecimal table

(Hexadecimal number is shown with H.)

In MIDI documentation, data values and addresses/sizes of system exclusive messages etc. are expressed as hexadecimal values for each 7 bits.

The following table shows how these correspond to decimal numbers.

+——————+——————++——————+——————++——————+——————++——————+——————+ Deci Hexa Deci Hexa Deci Hexa Deci Hexa +——————+——————++——————+——————++——————+——————++——————+——————+

0	00H	32	20H	64	40H	96	60H
1	01H	33	21H	65	41H	97	61H
2	02H	34	22H	66	42H	98	62H
3	03H	35	23H	67	43H	99	63H
4	04H	36	24H	68	44H	100	64H
5	05H	37	25H	69	45H	101	65H
6	06H	38	26H	70	46H	102	66H
7	07H	39	27H	71	47H	103	67H
8	08H	40	28H	72	48H	104	68H
9	09H	41	29H	73	49H	105	69H
10	0AH	42	2AH	74	4AH	106	6AH
11	0BH	43	2BH	75	4BH	107	6BH
12	0CH	44	2CH	76	4CH	108	6CH
13	0DH	45	2DH	77	4DH	109	6DH
14	0EH	46	2EH	78	4EH	110	6EH
15	0FH	47	2FH	79	4FH	111	6FH
16	10H	48	30H	80	50H	112	70H
17	11H	49	31H	81	51H	113	71H
18	12H	50	32H	82	52H	114	72H
19	13H	51	33H	83	53H	115	73H
20	14H	52	34H	84	54H	116	74H
21	15H	53	35H	85	55H	117	75H
22	16H	54	36H	86	56H	118	76H
23	17H	55	37H	87	57H	119	77H
24	18H	56	38H	88	58H	120	78H
25	19H	57	39H	89	59H	121	79H
26	1AH	58	3AH	90	5AH	122	7AH
27	1BH	59	3BH	91	5BH	123	7BH
28	1CH	60	3CH	92	5CH	124	7CH
29	1DH	61	3DH	93	5DH	125	7DH
30	1EH	62	3EH	94	5EH	126	7EH
31	1FH	63	3FH	95	5FH	127	7FH

+——————+——————++——————+——————++——————+——————++——————+——————+

How to calculate checksum (Hexadecimal number is shown with H.)

Checksum is a value which lower 7 bit of the sum of address, size and checksum itself turns to be 0.

If the address of the system exclusive message to be transmitted is aa bb ccH and data or size is dd ee ffH,

aa+ bb + cc + dd + ee + ff = sum sum / 128 = quotient and odd When odd is 0, 0 = checksum

When odd is other than 0, 128 - odd = checksum

*Decimal values such as MIDI channel, bank select, and program change are listed as one (1) greater than the values given in the above table.

*A 7-bit byte can express data in the range of 128 steps. For data where greater

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