User`s manual

FX communication
FX
2N
-232IF 10
10-8
10.2.3 Command
〈
BFM #1
〉
BFM #1 gives the command for send/receive and the status information reset command to the
232IF.
1 ) b0 (send/receive enable)
While b0 is turned on, the 232IF can send and receive data.
The contents of the following setting items are determined on the rising edge of b0. Make
sure to set the contents using the TO instruction before setting b0 to “ON”.
• BFM #0 (communication format)
• BFMs #9 and #8 (receive header)
• BFMs #11 and #10 (receive terminator)
On the rising edge of b0, the error occurrence (BFM #28 b3) and the error code (BFM #29)
are cleared.
2 ) b1 (send command)
On the rising edge of b1, the contents of the send buffers (BFMs # 1001 to #1256) are sent to
the counterpart equipment up to the send byte count (BFM #1000).
When send is completed, the send completion status (BFM #28 b0) is set. BFM #28 b0 is
automatically reset when the next send command (b1) is given.
When b1 is given, the contents of the following setting items are determined.
• BFMs #5 and #4 (send header)
• BFMs #7 and #6 (send terminator)
3 ) b2 (receive completion reset command)
When b2 is set to “ON”, the following items are cleared.
• BFM #28 b1 (receive completion)
• BFM #2000 (receive byte count)
• BFMs #2001 to #2256 (receive buffers)
When receive is completed, b2 should be set to “ON” to clear the receive completion status
(BFM #28 b1). If BFM #28 b1 is not reset, the next data cannot be received.
When b2 is set to “ON”, the contents of the following setting items are determined.
• BFMs #9 and #8 (receive header)
• BFMs #11 and #10 (receive terminator)
In the RS-232C interlink connection mode (BFM #0 b9=1, b8=1), b2 functions as the receive
continuation command to receive data exceeding the receive upper limit byte count (BFM
#2), and clears the following items.
• BFM #28 b4 (receive suspended)
• BFM #2000 (receive byte count)
• BFMs #2001 to #2256 (receive buffers)
• BFMs #2257 to #2271 (spare receive buffers)
When b2 is set to “ON”, the request to send (RS) signal is automatically set to “ON” also.
4 ) b3 (error reset)
When b3 is set to “ON”, the error occurrence status (BFM #28 b3) and error code (BFM #29)
are cleared.
Bit Description
b0 Send/receive enable (ER ON)
b1 Send command
b2 Receive completion reset command
b3 Error reset