Communication Format <Bfm #0> - Mitsubishi Electric FX3U-232-BD User Manual

FX Series PLC User's Manual - Data Communication Edition
Non-Protocol Communication (FX
5.4.2 Communication format <BFM #0>
Bit
b0 Data length
b1
Parity
b2
b3 Stop bit
b4
b5
Baud rate (bps)
b6
b7
b8
Control line
b9
b10
CR and LF addition
b11
b12 Absence/presence of check sum
b13 and ASCII-Hexadecimal conversion
Send/receive data buffer data
b14
length
b15 Undefined (cannot be used)
The communication format setting contents are determined when the sending/receiving enable command
(BFM #1, b0) turns ON.
Accordingly, it is necessary to transfer the communication format setting in advance using TO instruction
before setting the sending/receiving enable command to ON.
However, the sending header and sending terminator are determined when the sending command (BFM #1,
b1) turns ON. And the receiving header and receiving terminator are determined when the sending/receiving
enable command (BFM #1, b0) turns ON and the receiving complete flag reset command (BFM #1, b2) turns
ON. Accordingly, if only the header and terminator are changed in the middle of communication, such change
will become valid at the next sending/receiving operation, (so it is not necessary to turn OFF the sending/
receiving enable command).
Example of communication format setting (specified in hexadecimal constant)
When specifying the communication format as shown in the table below, use the following program.
Data length
Parity
Stop bit
Baud rate
Control line
CR and LF
Check sum
ASCII-hexadecimal
conversion
Buffer data length
G-20
-232IF)
2N
Contents
7-bit
(00) : Not provided
(01) : Odd
(11) : Even
1-bit
(0011) : 300
(0100) : 600
(0101) : 1200
(0110) : 2400
(0111) : 4800
(1000) : 9600
(1001) : 19200
(00) : Not provided
(01) : Standard RS-232C
(11) : RS-232C interlink mode
(00) : Both CR and LF are not added.
(01) : Only CR is added.
(11) : Both CR and LF are added.
(00) : Both check sum and ASCII-hexadecimal
conversion are not provided.
(01) : Only ASCII-hexadecimal conversion is
provided.
(10) : Only check sum is provided.
(11) : Both check sum and ASCII-hexadecimal
conversion are provided.
16-bit
8-bit
Odd
1-bit
2400 bps
Not provided
Not added
Not provided
Not provided
8-bit
0
8-bit
2-bit
8-bit
—
M8002
FNC 79
K 0
TO
Initial pulse
Block No. BFM # Set value Number of
b15 b12 b11
BFM #0 0 1 0 0 0
4
5 Creating Programs
5.4 Buffer Memory (BFM)
1 Initial value
1 : 8-bit
(11) : Even
0 : 1-bit
(1000) : 9600 bps
(00) : Not provided
(00) : Not provided
(00) : Not provided
0 : 16-bit
0 : Undefined
K 0 H4063 K 1
transfer
points
b8 b7 b4 b3
0 0 0 0 1 1 0 0
0 6
(4063H)
b0
0 1 1
3