Programming - CommTech FASTCOM SuperFASTCOM Hardware Reference Manual

14

PROGRAMMING

Refer to the enclosed FASTCOM CD for example programs, product updates, and software for
testing your installation.
information.
Local Bus Interface for PEB 20534 - Byte accesses
Register at offset 0
Channel 1
1 = receive constantly enabled
Bit 0
0 = receive enabled only when RTS is off
1 = transmit constantly enabled
Bit 1
0 = transmit enabled only when RTS is on
1 = TT constantly enabled
Bit 2
0 = TT enabled only when RTS is on
Bit 3 No function
Channel 2
1 = receive constantly enabled
Bit 4
0 = receive enabled only when RTS is off
1 = transmit constantly enabled
Bit 5
0 = transmit enabled only when RTS is on
1 = TT constantly enabled
Bit 6
0 = TT enabled only when RTS is on
Bit 7 No function
Register at offset 2
Channel 1
0 = ST connected to TXCLK
Bit 0
1 = ST not connected
0 = TT connected to TXCLK
Bit 1
1 = TT not connected
Channel 2
0 = ST connected to TXCLK
Bit 2
1 = ST not connected
0 = TT connected to TXCLK
Bit 3
1 = TT not connected
Offset 0 & 1 – These bits are generally for choosing between 422 and 485 communications.
Receive constantly enabled – (default) for RS-422 communication
Receive enabled only when RTS is off – also Rx Echo Cancel; disables the receiver
when transmitting so that you do not receive everything that you transmit when using 2-
wire RS-485.
Transmit constantly enabled – (default) for RS-422 communication
Transmit enabled only when RTS is on – turns off the transmitter when it is not actively
sending data so that it does not contend with another transmitter on the data bus
Refer to the Infineon PEB 20534 User's Manual for register
Register at offset 1
Channel 3
1 = receive constantly enabled
Bit 0
0 = receive enabled only when RTS is off
1 = transmit constantly enabled
Bit 1
0 = transmit enabled only when RTS is on
1 = TT constantly enabled
Bit 2
0 = TT enabled only when RTS is on
Bit 3 No function
Channel 4
1 = receive constantly enabled
Bit 4
0 = receive enabled only when RTS is off
1 = transmit constantly enabled
Bit 5
0 = transmit enabled only when RTS is on
1 = TT constantly enabled
Bit 6
0 = TT enabled only when RTS is on
Bit 7 No function
Channel 3
0 = ST connected to TXCLK
Bit 4
1 = ST not connected
0 = TT connected to TXCLK
Bit 5
1 = TT not connected
Channel 4
0 = ST connected to TXCLK
Bit 6
1 = ST not connected
0 = TT connected to TXCLK
Bit 7
1 = TT not connected