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Instructions having indexed addresses, Instructions having m0 or m1 data file addresses – Rockwell Automation 1747-PT1, D1747NP002 Hand-Held Terminal User Manual

Page 463

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Instruction Execution Times

Appendix C
Memory Usage,

C–9

Instructions Having Indexed Addresses

For each operand having an indexed address, add 50 microseconds to the
execution time for a true instruction. For example, if a MOV instruction has
an indexed address for both the source and destination, the execution time
when the instruction is true is 24 + 50 + 50 = 124 microseconds.

Instructions Having M0 or M1 Data File Addresses

For each bit or word instruction, add 1928 microseconds to the execution
time. For each multiple-word instruction, add 1583 microseconds plus 667
microseconds per word.

]/[

M1:3.1

1

] [

M0:2.1

1

( )

M0:2.1

10

MOV

MOVE
Source

M1:10.7

Dest

N7:10

Example

COP

COPY FILE
Source

#B3:0

Dest

#M0:1.0

Length

34

For the multi–word instruction above, add 1583 microseconds plus 667
microseconds per word. In this example, 34 words are copied from #B3:0 to
M0:1.0. Add 1583 + (667 x 34) = 24261 microseconds to the execution time
listed on page C–8. This comes to 763 (calculated from page C–8 table) plus
24261 = 25024 microseconds total, or 25.0 milliseconds.