130
Serial Communications Instructions Section 3-22
3-22 Serial Communications Instructions
INTELLIGENT I/O
WRITE
IOWR
@IOWR
223
Output
Required
CPU BUS UNIT
I/O REFRESH
(CS1-H, CJ1-H,
or CJ1M only)
DLNK
@DLNK
226
Immediately refreshes the I/O in the CPU Bus Unit with the specified unit num-
ber.
Output
required
Instruction
Mnemonic
Code
Symbol/Operand Function Location
Execution
condition
PROTOCOL
MACRO
PMCR
@PMCR
260
Output
Required
TRANSMIT
TXD
@TXD
236
Outputs the specified number of bytes of data from the RS-232C port built into
the CPU Unit.
Output
Required
Instruction
Mnemonic
Code
Symbol/Operand Function Location
Execution
condition
C: Control data
S: Transfer
source and
number of words
D: Transfer
destination and
number of words
IOWR(223)
C
S
D
Desig-
nated
number of
words writ-
ten.
D
D+1
Unit number of Special I/O Unit
Outputs the contents of the CPU Unit's I/O memory area to the Special I/O
Unit.
C1:Control word 1
C2: Control word 2
S: 1st send word
R: 1st receive word
PMCR(260)
C1
C2
S
R
to
to
R
CPU Unit Serial Communications Unit
External
device
Port
S
Calls and executes a communications sequence registered in a Serial
Communications Board (CS Series only) or Unit
Communications
sequence number
S: 1st source
word
C: Control word
N: Number of
bytes
0000 to 0100 hex
(0 to 256 decimal)
TXD(236)
S
C
N