●
For data transmission to be effective it is necessary to match the communication format between the product and the
RS232C device, such as baud rate and parity.
*1 The default value is STX (02H: changeable).
*2 The default value is ETX (03H: changeable).
●
The communication format is set by special data register D8120.
Setting the communication format using D8120 is effective only at the time the RS instruction is driven, and therefore
if changed after driving, it is not actually accepted.
●
An example of setting D8120 is shown below.
●
The control line is set by b12.
b12=0 :No hardware hand shaking.Send and receive are controlled by software protocol.
b12=1 :Hardware hand shaking.Signal lines ER(DTR)and DR(DSR)are used to control send and receive of data.
H138F= 0001 0011 1000 1111(binary)
The settings for the above program are as right.
b0
b12 1
b11 0
SD(TXD)
H/W.
Ordinary
mode
Pin No.
ER(DTR)
DR(DSR)
When sending
RD(RXD)
ER(DTR)
DR(DSR)
When receiving
Pin No.
Data
SD(TXD)
RD(RXD)
ER(DTR)
b12 1
b11 1
H/W.
Single line
mode
Pin No.
Data
Send
Send
Receive
Data
Receive
Data
[MOV
D8120]
H138F
Bit
Description
0 (OFF)
1 (ON)
b 8
Header
None
D8124 *1
b 9
Terminator
None
D8125 *2
b10
Not used
- - -
- - -
b11
Mode
(Control line)
Ordinary
mode
Single line
mode
b12
Control line
None
H/W
b13
b14
b15
Not used
- - -
- - -
Data length
8 bit
Parity
Even
Stop
2 bit
Baud rate
9,600
Header
Used
Terminator
Used
Control line
H/W
Mode
Ordinary mode
Bit
Description
0 (OFF)
1 (ON)
b 0
Data length
7bit
8bit
b 1
b 2
Parity
(00) : None
(01) : Odd
(11) : Even
b 3
Stop
1bit
2bit
b 4
b 5
b 6
b 7
Baud rate
(bps)
(0011) : 300
(0100) : 600
(0101) : 1,200
(0110) : 2,400
(0111) : 4,800
(1000) : 9,600
(1001) : 19,200
Communication format D8120 (bit mapping)
M8002
Setting input
