Using No-Protocol Communications; Transmit - Txd( ) And Receive - Rxd( ) - Omron CQM1H-SCB41 Operation Manual

Using No-protocol Communications

6-4

Using No-protocol Communications

6-4-1 TRANSMIT – TXD( ) and RECEIVE – RXD( )
TRANSMIT – TXD( ) in No-protocol Mode
Control Word: C
104
This section describes using TXD( ) and RXD( ) for no-protocol communi-
cations.
15 00
0 0
The specified number of bytes will be read starting from S and transmitted
through the specified port.
• Up to 256 bytes of data can be sent each time the instruction is executed.
• The bytes of source data shown below will be sent in the following order.
If most significant bytes first is specified (0): 12345678..
If least significant bytes first is specified (1): 21436587..
Communications parameters are set in the PC Setup settings for the Serial
Communications Board. Refer to information in the CQM1H Programming
Manual on serial communications and TXD( ) for details.
TXD( )
First source word
S
Control word
C
Number of bytes
N
(4 digits BCD, 0000 to 0256)
Byte order 0: Most significant bytes first
1: Least significant bytes first
Not used. (Set to 0.)
Port 0: RS-232C port on CPU Unit
1: Port 1 on Serial Communications Board
2: Port 2 on Serial Communications Board
Not used. (Set to 0.)
MSB LSB
S 1 2
S+1 3 4
S+2 5 6
S+3 7 8
Section 6-4