Omron SYSMAC C200H-IDS01-V1 Operation Manual page 33

The User Program
Writing Data to the Data
Carrier from the CPU
CPU
Reading Data from the
Data Carrier to the CPU
CPU
18
The CPU, via the Write, Auto Write, and Clear-all commands, directs the ID
Sensor Unit to write data to the Data Carrier. The following diagram shows
how the program writes data to the Data Carrier.
1 2
ID Sensor
Unit
3b
4
1. The CPU sends the command data (the number of words in the com-
mand to be sent, the beginning word number of the command, and
the command execution start) to the ID Sensor Unit by using MOV or
OUT.
2. The ID Sensor Unit analyzes the command received from the CPU.
3a. If the command is legal, the ID Sensor Unit writes the required data to
the Data Carrier.
3b. If the command is illegal, the ID Sensor Unit sets the Command Error
flag (word n+4 bit 09) to ON and returns the data to the CPU. At this
time, the ID Busy flag (word n+4 bit 00) is turned OFF.
4. When the ID Sensor Unit has completed communication with the
Data Carrier, the Unit turns OFF the ID Busy flag as the command is
completed, and returns the data to the CPU.
If communication with the Data Carrier fails, or if an error occurs during com-
munication, the ID Sensor Unit stops data communication with the Data Car-
rier, turns ON the Data Carrier communication error flags, returns the data to
the PC, and turns OFF the ID Busy flag.
Steps 1 to 4 compose one write operation.
The CPU, via the Read and Auto Read commands, directs the ID Sensor Unit
to read data from the Data Carrier to the CPU. The following diagram shows
how the program reads data from the Data Carrier.
1 2
ID Sensor
Unit
3b
4
1. The CPU sends command data (the number of words in the com-
mand, the beginning word number of the command, and the begin-
ning word number of the data to be received) to the ID Sensor Unit by
using MOV or OUT.
2. The ID Sensor Unit analyzes the command received from the CPU.
3a. If the command is legal, the ID Sensor Unit reads the required data to
the Data Carrier.
3a
R/W
Head
3a
R/W
Head
Section 2-3
Data
Carrier
Data
Carrier