Mitsubishi Q00CPU, Руководство пользователя

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App
- 143 Appendix 5 Method of replacing High Performance model QCPU with Universal model QCPU
APPENDICES
(4) Method of replacing High Performance model QCPU with Universal
model QCPU
(a) Replacing all single-precision floating-point operation instructions with
double-precision floating-point operation instructions
Single-precision floating-point data occupy two points of word device per data. On
the other hand, four points are required per double-precision floating-point data.
Therefore, all device numbers for storing floating-point data need to be
reassigned.
Example) Replacing the floating-point operation [A to B+C] (Changing all
floating-point data into double precision.)
1) Device assignment
2) Program before replacement
3) Program after replacement
TableApp.75 Device assignment
Before replacement After replacement
Application Device Data type Application Device Data type
Data A D0 to D1
Floating-point
data (single
precision)
Data A D0 to D3
Floating-point
data (double
precision)
Data B D2 to D3 Data B D4 to D7
Data C D4 to D5 Data C D8 to D11
Data D D6 to D7 Data D D12 to D15
Figure App.20 Sample program
Figure App.21 Sample program
Operation is performed using
double-precision floating-point
data.