Omron V670 Series, User Manual

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5-6 Communication Command
5-12
5-6-3 Computation Write (CW)
Performs the computation of data in tag memory and computation data in a hexadecimal number and writes the result into the tag. If
overflow and underflow occurs in addition and subtraction, respectively, no data is written and "1" is returned to the status flag.
Example: Subtracting the computation data ("0002") from 2 bytes data ("0010") in the address 0001h and writing the result
(Single trigger, initial value "0010")
Sent data: CWSTS 1 0 0 0 1 0 2 0 0 0 2 * [CR]
Received data: CW 0 0 0 0 0 0 0 E * [CR]
Communication designation Specifies how to communicate with a tag. For details, refer to the communication desig-
nation list.
Process designation Specifies how to compute.
"A": Hexadecimal addition
"S": Hexadecimal subtraction
Antenna designation Fixed to "1".
First address of computation
area Specifies the first address of area, where data is computed, in four hexadecimal digits.
Available designation range: 0000h to 007Fh.
Number of addition area
bytes Specifies the number of bytes of area, where data is computed, in two hexadecimal dig-
its.
Available designation range: 01h to 04h.
Computation data Specifies a numerical value to be computed in a hexadecimal number.
Result data Returns a calculation result data written into the tag. If overflow and underflow occurs in addition
and subtraction, respectively, the result data is a data before the calculation. In this case, the sta-
tus flag is "1".
Correct Usage
This command performs the hexadecimal computation. So, you must specify all the data in a hexadecimal code. More-
over, specify an addition area within one page. Otherwise, a command error occurs.
<Command>
Command
code
"CW"
Communication
designation
Process
designa-
tion Antenna
designa-
tion The first address of computation
area
The number of
computation
area bytes
Computation data
Number of specified bytes
<Response>
Command
code
"CW"
Termination
code
"00"
Retrans-
mission
flag
Status
flag
Result data
Number of specified bytes