B&B Electronics 232BSS4 - Manual - Manual (Page 13)

Documentation Number 232BSS4-0812m 9
&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104 – www.bb-elec.com
B&B Electronics – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph +353 91-792444 – Fax +353 91-792445 – www.bb-europe.com
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.