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3 CONFIGURATION OF INSTRUCTIONS
3.6 Cautions on Programming (Operation Errors)
Device data check
Device data checks for the devices used by basic instructions and application instructions in CPU module are as indicated
below:
■When using BIN data
No error is returned even if the operation results in overflow or underflow. The carry flag (SM700) does not go on at such
times, either.
■When using BCD data
• Each digit is check for BCD value (0 to 9). An operation error is returned if individual digits are outside the 0 to 9 (A to F)
range.
• No error is returned even if the operation results in overflow or underflow. The carry flag (SM700) does not go on at such
times, either.
■When using floating-point data
• An operation error occurs when the following operation results are returned with the single-precision floating-point
operation instruction.
When the absolute value of the floating decimal point data is 1.0 2
-127
or lower
When absolute value of floating decimal point data is 1.0 2
128
or higher
• An operation error occurs when the following operation results are returned with the double-precision floating-point
operation instruction.
When the absolute value of the floating decimal point data is 1.0 2
-1023
or lower
When absolute value of floating decimal point data is 1.0 2
1024
or higher
■Using character string data
No data check is conducted.
Buffer memory access
For accessing buffer memories, using instructions with intelligent function module devices (from Un\G0) is recommended.
Multiple CPU shared memory access
For accessing multiple CPU shared memories, using instructions with multiple CPU shared devices (from U3En\G10000) is
recommended.
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