Communication Protocol
NOTE 3
The reply to a “ REQUEST” instruction is as follows: the same instruction and input codes as were sent are returned, and the OUTPUT is assigned to the value of the requested parameter. The reply to the instruction #5 (what is the status of the VGA group?):
0000 0101
1000 0000
1000 0011
1000 0001 Would be:
0100 0101
1000 0000
1000 0100
1000 0001
NOTE 4
An error code is returned to the PC if an invalid code was sent to the switcher (for example, when trying to switch an input or a group which is greater than the highest one defined). This code is also returned to the PC if an
NOTE 5
Under normal conditions, the machine’ s present status is saved each time a change is made. The
NOTE 6
This is a request to identify the switchers in a system. If the INPUT is set as 1 or 2, the machine will send its name. The reply is the decimal value of the INPUT and the OUTPUT. For example, the reply to the request to send the machine’ s name (for machine #001) will be:
0111 1101 |
|
1000 0000 | (i.e. 128+0) |
1001 0111 | (i.e. 128+23) |
1000 0001
If the request for identification is sent with the INPUT set as 3 or 4, the appropriate machine will send its software version number. Again, the reply would be the decimal value of the INPUT and OUTPUT - the INPUT representing the number in front of the decimal point, and the OUTPUT representing the number following the decimal point. For example, for version
3.5the reply will be: 0111 1101
1000 0011 (i.e. 128+3)
1000 0101 (i.e. 128+5)
1000 0001
NOTE 7
GAIN VALUE – Number from 0 to 127
NOTE 8
Answer = Current Audio Gain (0
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