Timbre parameter messages are provided to permit interrogating and changing of the parameters that control the timbre of a given voice. Parameters are addressed using three 7-bit bytes (that is, 21 bits), enabling approximately two million parameters to be addressed. In most cases, these parameters are divided into units such as banks, voices, and so forth. Parameter values are passed in two 7-bit bytes, allowing up to 14-bits per parameter.
The following are types of timbre parameter messages:
Query Timbre Parameter
This message is issued to a device driver by an application to request the current setting of a timbre parameter:
F0 00 00 3A 06 01 hh mm ll F7 hh = High 7-bits parameter # mm = Middle 7-bits parameter # ll = Low 7-bits parameter #
The device driver responds to this message by returning a timbre parameter response message (see below).
Request Timbre Block
This message is issued to a device driver by an application to request a block of timbre data.
F0 00 00 3A 06 04 hh mm 00 F7 hh = High 7-bits block # mm = Middle 7-bits block #
The device driver responds to this message by returning a timbre block message (see below).
Set Timbre Parameter
This message is used to set or change a timbre parameter:
F0 00 00 3A 06 03 hh mm ll dl dm F7 hh = High 7-bits parameter # mm = Middle 7-bits parameter # ll = Low 7-bits parameter # dl = Parameter data LSB (0-127) dm = Parameter data MSB
Timbre Block
This message is issued by a device driver in response to a request timber block message (see above). It transfers blocks of timbre data from a device driver to an application.
F0 00 00 3A 06 05 hh mm ll < len > F7 hh = High 7-bits block # mm = Middle 7-bits block # ll = Length of 7-bit data < len > = Variable length (7-bit) data block
Timbre Parameter Response
This message is sent by a device driver in response to a query timbre parameter message (see above). It returns the current value of a timbre parameter.
F0 00 00 3A 06 02 hh mm ll dl dm F7 hh = High 7-bits parameter # mm = Middle 7-bits parameter # ll = Low 7-bits parameter # dl = Parameter data LSB (0-127) dm = Parameter data MSB
Write Timbre Block
This message is issued to a device driver by an application to write a block of timbre data:
F0 00 00 3A 06 06 hh mm ll < len > F7 hh = High 7-bits block # mm = Middle 7-bits block # ll = Length of 7-bit data < len > = Variable length (7-bit) data block