MIDI Implementation

Example of an Exclusive message and calculating a checksum

Roland Exclusive messages (RQ1, DT1) are transmitted with a checksum at the end (before F7) to make sure that the message was correctly received. The value of the checksum is determined by the address and data (or size) of the transmitted Exclusive message.

How to calculate the checksum (hexadecimal numbers are indicated by

“H”)

The checksum is a value derived by adding the address, size, and checksum itself and inverting the lower 7 bits.

Here's an example of how the checksum is calculated. We will assume that in the Exclusive message we are transmitting, the address is aa bb cc ddH and the data or size is ee ffH.

aa+ bb + cc + dd + ee + ff = sum sum ÷ 128 = quotient ... remainder 128 - remainder = checksum

<Example 1> Setting CHORUS TYPE of PERFORMANCE COMMON to DELAY (DT1). According to the “Parameter Address Map (p. 181),” the start address of Temporary Performance is 10 00 00 00H, the offset address of CHORUS at PERFORMANCE COMMON is 04 00H, and the address of CHORUS TYPE is 00 00H. Therefore the address of CHORUS TYPE of PERFORMANCE COMMON is;

10 00

00

00H

 

04

00H

+)

00

00H

10 00

04

00H

DELAY has the value of 02H.

So the system exclusive message should be sent is;

F0

41

10

00 10

12

10 00 04 00

02

??

F7

(1)

(2)

(3)

(4)

(5)

address

data

checksum

(6)

(1) Exclusive Status,

(2) ID (Roland),

(3) Device ID (17),

 

(4) Model ID (XV-3080),

(5) Command ID (DT1),

(6) End of Exclusive

 

Then calculate the checksum.

10H + 00H + 04H + 00H + 02H = 16 + 0 + 4 + 0 + 2 = 22 (sum)

22 (sum) ÷ 128 = 0 (quotient) ... 22 (remainder) checksum = 128 - 22 (remainder) = 106 = 6AH

This means that F0 41 10 00 10 12 10 00 04 00 02 6A F7 is the message should be sent.

<Example 2> Getting the data (RQ1) of Performance Part 3 in USER:03.

According to the “Parameter Address Map (p. 181),” the start address of USER:03 is 20 02 00 00H, and the offset address of Performance Part 3 is 00 22 00H.

Therefore the start address of Performance Part 3 in USER:03 is;

20

02 00

00H

+)

00 22

00H

20

02 22

00H

As the size of Performance Part is 00 00 00 21H, the system exclusive message should be sent is;

F0

41

10

00 10

11

20 02 22 00

00 00 00 21

??

F7

(1)

(2)

(3)

(4)

(5)

address

data

checksum

(6)

(1) Exclusive Status,

(2) ID (Roland),

 

(3) Device ID (17),

 

(4) Model ID (XV-3080),

(5) Command ID(RQ1),

(6) End of Exclusive

 

Then calculate the checksum.

20H + 02H + 22H + 00H + 00H + 00H + 00H + 21H = 32 + 2 + 34 + 0 + 0 + 0 + 0 + 33 = 101 (sum)

101 (sum) ÷ 128 = 0 (quotient) ... 101 (remainder) checksum = 128 - 101 (remainder) = 27 = 1BH

This means that F0 41 10 00 10 11 20 02 22 00 00 00 00 21 1B F7 is the message should be sent.

<Example 3> Getting Temporary Performance data (RQ1);

cf.) This operation is the same as Data Transfer function in Utility mode with “PERFORM” (Type parameter) and “TEMP: -PATCH” (Source parameter) options.

According to the “Parameter Address Map (p. 181),” the start address of Temporary Performance is assinged as following:

10 00 00 00H Temporary Performance Common

:

10 00 20 00H Temporary Performance Part 1

:

10 00 2F 00H Temporary Performance Part 16

As the data size of Performance Part is 00 00 00 21H, summation of the size and the start address of Part 16 at Temporay Performance will be;

10 00 2F 00H

+) 00 00 00 21H

10 00 2F 21H

And the size that have to be got should be;

10 00 2F 21H

-) 10 00 00 00H

00 00 2F 21H

Therefore the system exclusive message should be sent is;

F0

41

10

00 10

11

10 00 00 00

00 00 2F 21

??

F7

(1)

(2)

(3)

(4)

(5)

address

data

 

checksum

6)

(1) Exclusive Status,

(2) ID (Roland),

 

(3) Device ID (17),

 

(4) Model ID (XV-3080),

(5) Command ID (RQ1),

(6) End of Exclusive

 

Calculating the checksum as shown in <Example 2>, we get a message of F0 41 10 01 10 11 10 00 00 00 00 00 2F 21 20 F7 to be transmitted.

<Example 4> Getting data (RQ1) at once; Tempory Performance data,

Temporary Patch data of whole part in Performance mode,

Temporary Rhythm data of whole part in Performance mode.

cf.) This operation is the same as Data Transfer function in Utility mode with “PERFORM” (Type parameter) and “TEMP: +PATCH” (Source parameter) options.

According to the “Parameter Address Map (p. 181),” the start address of the above all parameters is assinged as following:

10 00 00 00H Temporary Performance

11 20 00 00H Temporary Patch (Performance Mode Part 1)

11 30 00 00H Temporary Rhythm (Performance Mode Part 1)

:

14 60 00 00H Temporary Patch (Performance Mode Part 16)

14 70 00 00H Temporary Rhythm (Performance Mode Part 16)

The offset address of Rhythm is also assigned as follows:

00

00 00H

Rhythm Common

 

:

 

00

10 00H

Rhythm Tone 1

 

:

 

01

3E 00H

Rhythm Tone 4

As the data size of Rhythm Tone is 00 00 01 41H, summation of the size and the start address of Tone 4 of Part 16 at Temporay Patch in Performance mode will be;

14 70 00 00H

01 3E 00H

+) 00 00 01 41H

14 71 3F 41H

And the size that have to be got should be;

14 71 3F 41H -) 10 00 00 00H 04 71 3F 41H

Therefore the system exclusive message should be sent is;

F0

41

10

00 10

11 10 00 00 00

04 71 3F 41

??

F7

(1)

(2)

(3)

(4)

(5) address

data

 

checksum

(6)

(1) Exclusive Status,

(2) ID (Roland),

 

(3) Device ID (17),

 

(4) Model ID (XV-3080),

(5) Command ID (RQ1),

(6) End of Exclusive

 

Calculating the checksum as shown in <Example 2>, we get a message of F0 41 10 00 10 11 10 00 00 00 04 71 3F 41 7B F7 to be transmitted.

Appendices

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Page 193
Image 193
Roland XV-3080 owner manual 193, Example of an Exclusive message and calculating a checksum

XV-3080 specifications

The Roland XV-3080 is a powerful and versatile sound module that has become a favorite among musicians, producers, and composers since its release in the late 1990s. This module is renowned for its extensive sound library, advanced synthesis capabilities, and user-friendly interface, making it a staple in studios and on stages worldwide.

One of the standout features of the XV-3080 is its impressive range of sounds. It boasts 1,024 preset sounds and 256 user patches, which can be expanded with Roland's SR-JV80 expansion boards to access even more diverse sounds. The XV-3080 is equipped with a Waveform Memory of 128 MB, providing high-quality samples and ensuring rich, detailed sound. The module also features a powerful multitimbral engine, allowing up to 16 simultaneous parts to be played, making it an ideal choice for complex arrangements and live performances.

Another key technology in the XV-3080 is its advanced SuperNATURAL technology. This innovation enhances traditional sample playback by incorporating physical modeling, enabling more expressive and nuanced tones. Musicians can take advantage of features like dynamic layering and velocity-sensitive control, adding an organic quality that is often missing in digital instruments.

The built-in effects processor is another highlight, offering a wide range of high-quality effects, including reverb, chorus, flanger, and distortion. These effects can be applied to individual parts or used globally, allowing for creative sound design and customization. The XV-3080 also supports real-time editing, letting users tweak parameters on the fly, which is particularly useful in live settings.

Connectivity is plentiful on the XV-3080, with MIDI In/Out, as well as digital and analog outputs. This allows for seamless integration with other equipment, whether it's a DAW, a keyboard controller, or an audio interface.

The XV-3080's intuitive interface, featuring a bright LCD screen and a straightforward layout, makes navigating through options quick and easy. Musicians can spend less time fumbling with settings and more time focusing on their music.

In summary, the Roland XV-3080 is a sophisticated sound module that combines cutting-edge technology with user-friendly features. Its extensive sound library, advanced synthesis capabilities, and solid effects processing make it an essential tool for any serious musician or producer looking to create professional-quality music.