Two-Word Operation; Communications With Cpu Unit - Omron SYSMAC C Series Operation Manual

Two-word Operation

+
Sensor
0 V
4-3 Two-word Operation

4-3-1 Communications with CPU Unit

CPU
Unit
Current Input
C500-AD101
+Voltage/Current
input
– Current input
–Voltage/
Current input
Shield (analog 0 V)
Input impedance 250 Ω
Note 1. When using current input, short the negative voltage/current input terminal
to the negative current input terminal.
2. Use shielded twisted-pair cable for external connections.
The I/O READ and I/O WRITE instructions, READ and WRIT, are used for data
transfer between the C500-AD101 and the CPU Unit in two-word operation
mode.
WRIT instruction
IR/CIO n
READ instruction
IR/CIO n+1
OUT instruction
Output bits
IR/CIO n, Bit 03 to 15
LD instruction, etc.
Input bits
IR/CIO n+1, Bit 03 to 15
The I/O WRITE Instruction, WRIT, is executed when the instruction execution
conditions are ON and the A/D Busy Flag (IR/CIO n+1, Bit 00) and A/D Read
Completed Flag (IR/CIO n+1, Bit 01) are both OFF.
A NOP (No Operation) results if either the A/D Busy Flag or A/D Read Com-
pleted Flag is ON.
When execution of the instruction is complete, the PC Write Completed Flag (IR/
CIO n, Bit 01) turns ON temporarily (differential output) and the Equal Flag
(SR 6306, SR 25506, A50006) turn ON. Completion of WRIT instruction execu-
tion can be evaluated from the Equal Flag immediately after the WRIT instruc-
tion.
µPC251
Special instruction
Write data
Shared
memory
Read data
I/O
words
Section 4-3
To A/D
section
Analysis of spe-
cial instructions
and data transfer
between shared
memory and data
carrier.
Peak Reset
Peak Read
Unconfirmed Data
Peak
37