Chapter 5 Appendices

*The size of the requested data does not indicate the number of bytes that will make up a DT1 message, but represents the address fields where the requested data resides.

*Some models are subject to limitations in data format used for a single transaction. Requested data, for example, may have a limit in length or must be divided into predetermined address fields before it is exchanged across the interface.

*The same number of bytes comprises address and size data, which, however, vary with the Model ID.

*The error-checking process uses a checksum that provides a bit pattern where the last 7 bits are zero when values for an address, size, and that checksum are summed.

•Data set 1: DT1 (12H)

This message corresponds to the actual data transfer process.

Because every byte in the data is assigned a unique address, a DT1 message can convey the starting address of one or more bits of data as well as a series of data formatted in an address-dependent order.

The MIDI standards inhibit non real-time messages from interrupting an Exclusive one. This fact is inconvenient for devices that support a “soft-thru” function. To maintain compatibility with such devices, Roland has limited the DT1 to 256 bytes so that an excessively long message is sent out in separate ‘segments’.

Byte

Description

F0H

Exclusive Status

41H

Manufacturer ID (Roland)

DEV

Device ID

MDL

Model ID

12H

Command ID

aaH

Address MSB

 

LSB

ddH

Data MSB

 

LSB

sum

Check sum

F7H

End of exclusive

 

 

*A DT1 message is capable of providing only the valid data among those specified by an RQ1 message.

*Some models are subject to limitations in data format used for a single transaction. Requested data, for example, may have a limit in length or must be divided into predetermined address fields before it is exchanged across the interface.

*The number of bytes comprising address data varies from one Model ID to another.

*The error-checking process uses a checksum that provides a bit pattern where the last 7 bits are zero when values for an address, size, and that checksum are summed.

•Example of Message Transactions

•Device A sending data to Device B

Transfer of a DT1 message is all that takes place.

Device A

[Data set 1] * More than 20m sec time interval.

[Data set 1]

[Data set 1]

Device B

•Device B requesting data from Device A

Device B sends an RQ1 message to Device A.

Checking the message, Device A sends a DT1 message back to Device B.

Device A

[Data set 1] * More than 20m sec time interval.

[Data set 1]

Device B

[Request data]

[Data set 1]

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Roland GI-20 owner manual Data set 1 DT1 12H

GI-20 specifications

The Roland GI-20 is a groundbreaking MIDI guitar converter that allows electric guitarists to explore the vast world of MIDI technology. Designed to bridge the gap between traditional guitar playing and digital music production, the GI-20 transforms standard guitar signals into MIDI data, giving players access to a wide array of synthesized sounds and virtual instruments.

One of the main features of the GI-20 is its ability to track the guitar’s pitch with high accuracy. Utilizing Roland’s advanced technology, the device boasts rapid response times and minimal latency, ensuring that every note plucked or strummed is translated into MIDI in real-time. This precision is crucial for guitarists who wish to maintain their playing style while experimenting with synthesizers and sampled instruments.

In terms of connectivity, the Roland GI-20 is equipped with a 13-pin connector, allowing it to interface seamlessly with compatible Roland synths, sound modules, and other MIDI devices. Additionally, standard MIDI outputs enable connection to MIDI controllers and computers, providing an expansive toolkit for music creation.

The user interface is designed with simplicity in mind. A large LCD display allows for easy navigation of settings, while intuitive controls help players adjust parameters on the fly. Guitarists can also customize their performance by altering the sensitivity levels, enabling them to fine-tune how the device responds to their playing style.

The GI-20 offers an array of built-in sounds that mirror the capabilities of traditional synthesizers. These sounds can be layered or split into different tones based on the player’s preferences, offering a variety of sonic textures to enhance compositions. Furthermore, the ability to save and recall user settings allows for quick access to preferred configurations during live performances.

Another significant characteristic of the GI-20 is its compatibility with a wide range of guitars, including both electric and bass guitars. As long as the instrument is equipped with the appropriate pickup system, the GI-20 can effectively convert its output into MIDI signals.

In summary, the Roland GI-20 is a versatile and innovative tool for guitarists seeking to expand their creative horizons. With its accurate tracking, extensive connectivity, user-friendly interface, and a wealth of sounds, it unlocks the potential for guitarists to dive into the realms of electronic music and MIDI composition. Whether in the studio or on stage, the GI-20 opens up a world of possibilities for musicians looking to blend traditional guitar playing with modern technology.