Protocol Used for OMX-SW6x1B Communication
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10 Protocol Used for OMX-SW6x1B Communication
The protocol used for communication between the PC and the Master
OMX-SW6x1B
is defined as follows:
MSB
LSB
N7
N6
N5
N4
N3
N2
N1
N0
Where:
N7 is used for communication between the Slave and the Master only
and is always 0 for communication with the PC.
N6N5N4 is the binary value of the Machine we are addressing minus
one, e.g., if we wish to address the Master (Machine 1 by definition),
then N6N5N4 = 000, if we wish to address Machine 6, then N6N5N4 =
101.
N3N2N1N0 is the binary value of the input to be selected, i.e.
N3N2N1N0 = 0111 is equivalent to pressing switch 7 on the front panel.
Several special codes are also valid:
N3N2N1N0 = 1101 requests that the Machine being addressed sends its
present status to the PC, i.e. which input is selected on its front panel.
N3N2N1N0 = 1110 is an "OK" handshake, i.e. confirmation that the
instruction was received by the addressed Machine. (If the addressed
Machine is not present, then this confirmation is not sent to the PC).
Information sent from the Master to the PC is done using the same format, for
example:
0
Machine Number -1
New Switch Status
N7
N6N5N4
N3N2N1N0
The rate of data transfer is always 9600 baud, with no parity, 8 data bits and 1
stop bit.
