Program instructions
7.3 Communication
S7-200 SMART
182 System Manual, 09/2015, A5E03822230-AC
Receive buffer format (SMB86 to SMB94, and SMB186 to SMB194)
SMB86 SMB186 Receive message status byte
n: 1 = Receive message function terminated; user issued disable command.
r: 1 = Receive message function terminated; error in input parameters or missing start or end con-
dition.
e: 1 = End character received.
t: 1 = Receive message function terminated; timer expired.
c: 1 = Receive message function terminated; maximum character count achieved.
p: 1 = Receive message function terminated; a parity error.
SMB87 SMB187 Receive message control byte
en:
0 = Receive message function is disabled.
1 = Receive message function is enabled.
The enable/disable receive message bit is checked each time the RCV instruction is executed.
sc:
0 = Ignore SMB88 or SMB188.
1 = Use the value of SMB88 or SMB188 to detect start of message.
ec:
0 = Ignore SMB89 or SMB189.
1 = Use the value of SMB89 or SMB189 to detect end of message.
il:
0 = Ignore SMB90 or SMB190.
1 = Use the value of SMB90 or SMB190 to detect start of message.
c/m:
0 = Timer is an inter-character timer.
1 = Timer is a message timer.
tmr:
0 = Ignore SMW92 or SMW192.
1 = Terminate receive if the time period in SMW92 or SMW192 is exceeded.
bk:
0 = Ignore break conditions.
1 = Use break condition as start of message detection.
Start of message character.
End of message character.
SMW90 SMW190 Idle line time period given in milliseconds. The first character received after idle line time has ex-
pired is the start of a new message.
SMW92 SMW192 Inter-character/message timer time-out value given in milliseconds. If the time period is exceeded,
the receive message function is terminated.
SMB94 SMB194 Maximum number of characters to be received (1 to 255 bytes). This range must be set to the
expected maximum buffer size, even if the character count message termination is not used.
To Next Page
Loading...
Need help?
General
