TC-Helicon VoiceLive Sysex Manual - Manual

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TC-Helicon Vocal Technologies
www.tc-helicon.com
TC-IVL
VoiceLive MIDI System Exclusive Version 1.2
Hexadecimal Notation
Many values in this document are presented in hexadecimal notation.
Hexadecimal numbers will be prefixed with “0x”.
Example:
Hexadecimal 0x123 = Decimal 291
Decimal 123 = Hexadecimal 0x7B
VoiceLive SYSEX message format:
0xF0 MIDI System exclusive message start
0x00 3 byte manufactors ID for TC-Helicon
0x01 ...
0x38 ...
<Device ID> System exclusive device ID (user parameter)
0x4E VoiceLive model ID
<Message ID> VoiceLive message type identifier
<Data> Start of message data
... Variable number of data bytes based on message type
0xF7 MIDI System exclusive message terminator
Data Packing (24-bit words to 4x7-bit bytes)
The idea of packing data is to take a 24-bit value (the normal width of
parameters in VoiceLive) and represent it as 4 bytes of 7 bits each.
This is done because SYSEX data can only be 7 bits in size. The first
three bytes hold (in sequence) bits 0-6, 7-13 and 14-20 of the 24-bit
value. The fourth byte hold bits 21-23 of the 24-bit value with zeros
in the remaining bits.
For example, If the value of a 24-bit parameter is 614 (0x266), it
would look like “0x66 0x04 0x00 0x00” in a SYSEX message.
Byte1 0x66 = binary X1100110 (abcdefg)
Byte2 0x04 = binary X0000100 (hijklmn)
Byte3 0x00 = binary X0000000 (opqrstu)
Byte4 0x00 = binary X0000000 (****vwx)
Final 24-Bit Value:
vwxopqrs tuhijklm nabcdefg
Total = 00000000 00000010 01100110
= 0x0 0x2 0x66 = 0x000266