User Communication Error - IDEC FC4A-C10R2 User Manual

User Communication Error

When a user communication error occurs, a user communication error code is stored in the data register designated as a
transmit status in the TXD instruction or as a receive status in the RXD instruction. When multiple errors occur, the final
error code overwrites all preceding errors and is stored in the status data register.
The status data register also contains transmit/receive status code. To extract a user communication error code from the
status data register, divide the value by 16. The remainder is the user communication error code. See pages 17-11 and
17-23.
To correct the error, correct the user program by referring to the error causes described below:
User Communication Error Code
User
Communication
Error Code
Start inputs to more than 5 TXD instructions are
1
on simultaneously.
2 Transmission destination busy timeout
Start inputs to more than 5 RXD instructions with
3
a start delimiter are on simultaneously.
While a RXD instruction without a start delimiter
4 is executed, another RXD instruction with or with-
out a start delimiter is executed.
5
6
The first byte of received data does not match
7
the specified start delimiter.
When ASCII to binary or ASCII to BCD conversion
is specified in the receive format, any code other
8
than 0 to 9 and A to F is received. (These codes
are regarded as 0 during conversion.)
BCC calculated from the RXD instruction does
9 not match the BCC appended to the received
data.
The end delimiter code specified in the RXD
10 instruction does not match the received end
delimiter code.
Receive timeout between characters
(After receiving one byte of data, the next byte is
11
not received in the period specified for the
receive timeout value.)
Overrun error
12 (Before the receive processing is completed, the
next data is received.)
Framing error
13
(Detection error of start bit or stop bit)
Parity check error
14
(Error is found in the parity check.)
TXD1/RXD1 (or TXD2/RXD2) instruction is exe-
15 cuted while user protocol is not selected for port
1 (or port 2) in the Function Area Settings.
Error Cause
— Reserved —
— Reserved —
« FC4A M S U
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17: U C
SER OMMUNICATION
Transmit/Receive Completion Output
Transmit completion outputs of the first 5 TXD
instructions from the top of the ladder diagram
are turned on.
Goes on after busy timeout.
Among the first 5 RXD instructions from the top
of the ladder diagram, receive completion out-
puts of RXD instructions go on if the start delim-
iter matches the first byte of the received data.
The receive completion output of the RXD instruc-
tion at a smaller address goes on.
No effect on the receive completion output.
If incoming data with a matching start delimiter
is received subsequently, the receive completion
output goes on.
The receive completion output goes on.
The receive completion output goes on.
The receive completion output goes on.
The receive completion output goes on.
The receive completion output goes off.
No effect on the completion output.
No effect on the completion output.
No effect on the completion output.
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SER S ANUAL
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NSTRUCTIONS
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