415
Communications Instructions
Section 5-30
Flags
ER:
Indirectly addressed EM/DM word is non-existent.
(Content of
*
EM/
*
DM word is not BCD, or the EM/DM area boundary
has been exceeded.)
5-30 Communications Instructions
5-30-1 RECEIVE – RXD(47)
Limitations
D and D+(N
÷
2)–1 must be in the same data area.
DM 6144 to DM 6655 cannot be used for D or N.
N must be BCD from #0000 to #0256.
Description
When the execution condition is OFF, RXD(47) is not executed. When the
execution condition is ON, RXD(47) reads N bytes of data received at the port
specified in the control word, and then writes that data in words D to
D+(N
÷
2)–1. Up to 256 bytes of data can be read at one time.
If fewer than N bytes are received, the amount received will be read.
0
0
1
8
0
0
0
0
C+2: DM 0302
15
0
@CMND(
−−
)
DM 0100
DM 0200
DM 0300
00000
Address Instruction
Operands
00000
LD
00000
00001
AND
AR
0209
00002
SEND(90)
DM
0100
DM
0200
DM
0300
AR 0209
0
0
0
8
0
3
0
0
C+3: DM 0303
C+1: DM 0301
C: DM 0300
0
0
0
3
C+4: DM 0304
0
0
6
4
C+5: DM 0305
Bytes of command data: 0008 (8 decimal)
Bytes of response data: 0018 (24)
Transmit to the local network and the device itself
Node number 3, unit address 00 (CPU Unit)
Response requested, port number 0, 3 retries
Response monitoring time: 0064 hexadecimal (10 seconds)
8
2
0
0
0
A
0
0
S+2: DM 0102
15
0
0
1
0
1
0
0
0
A
S+3: DM 0103
S+1: DM 0101
S: DM 0100
Command code: 0101 hexadecimal (MEMORY AREA READ)
Number of words to read = 0A hexadecimal (10 decimal)
DM 0010 (Data area = 82 hexadecimal, address = 000A00)
D
:
First destination word
IR, SR, AR, DM, EM, HR, TIM/CNT, LR
C
:
Control word
#
Ladder Symbols
Operand Data Areas
N
:
Number of bytes
IR, SR, AR, DM, EM, HR, TIM/CNT, LR, #
RXD(47)
D
C
N
@RXD(47)
D
C
N
