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Parameter numbers 0xF0 (+256), 0xF1 (+512), 0xF2 (+768) are used to access parameters
whose numbers are 256 and higher. For example, to access the first parameter in the 256-511
range, use 0xF0 and 0x00.
Parameter Number
0 through 0xEF
0xF0, 0xF1, 0xF2
Host Requirements
Note: Due to the processing time of interpreting and storing parameters
contained in the message, it may not be possible for the decoder to
send an ACK within the programmable Serial Response time-out. It
should not be considered an error if the time-out is exceeded. To
compensate, increase the time-out.
The host transmits this message to change the decoder's parameters. Be sure the Change Type
bit in the Status byte is set as desired. If no beep is required, the beep code must be set to 0xFF,
or the decoder beeps as defined in Table 6-4.
Decoder Requirements
When the decoder receives a PARAM_SEND, it interprets and stores the parameters, then
ACKs the command (if ACK/NAK handshaking is enabled). These parameters are stored
permanently only if the Change Type (bit 3 of the Status byte) is set to 1. If bit 3 is set to 0
the changes are temporary, and are lost when the decoder is powered down.
If the PARAM_SEND sent by the host contains a valid beep code, the decoder issues the
requested beep sequence, and changes the requested parameter values.
The decoder issues a PARAM_SEND in response to a PARAM_REQUEST from the host. It
sends the values for all the supported parameter values requested in the PARAM_REQUEST
message. No value is sent for any unsupported param_num. If none of the requested values
is supported, the PARAM_SEND message is transmitted with no parameters. When sending
this command, the Change Type bit (bit 3 of Status byte) can be ignored.
Table 6-9. Param Data Format
<param_num> <value>
<extended parameter code> <param_num offset>
<value>
Simple Serial Interface
Data Format
6-25
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