Commands:
Select Port A to transmit and receive – “A”
Select Port B to transmit and receive – “B”
Select Port C to transmit and receive – “C”
Select Port D to transmit and receive – “D”
The Select Port commands turn on the selected port for both transmit and receive operations. Once the command is received by the switch, any data that had been buffered from the selected Slave device will be sent to the Master. Any data received on the Master port that is not a valid command sequence will be passed to the selected Slave port until another command is received.
For instance, to send and receive data from port B, send: {Char1}{Char2}{Char3}”B”
VB Example:
SwitchB$ = CHR$(27) & CHR$(2) & “B”
Turn Off all selected ports – ASCII EOT character (decimal 4)
The Turn Off command deselects all ports. No ports will transmit or receive to/from the Master port until another command is received by the Master port.
The full command sequence to disable all ports is: {Char1}{Char2}{Char3}EOT
VB Example:
OFF$ = CHR$(27) & CHR$(2) & CHR$(4)
Send Only to specific ports – “S” + one control byte specifying which ports to send.
The Send Only command will tell the 232BSS4 which Slave ports to send the following data to. This command can be used to broadcast data to more than one port at a time. The Slave port that is sending to the Master is not affected.
The lowest four bits of the control byte tell the 232BSS4 which ports should receive the following data. Bit 0 represents port A, Bit 1 represents port B, Bit 2 represents port C, and Bit 3 represents port D. In decimal, this is represents a value of 1, 2, 4, and 8 respectively. To turn on more than one port, the decimal equivalents of each port are added together to give the final byte.
Documentation Number | 9 |
&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph
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