Delta Tau GEO BRICK LV User Manual

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Turbo PMAC User Manual 
Making your Application Safe 
217 
The following table summarizes the different commands that can be used to stop motion and their 
attributes: 
Command Scope  Begin 
Immed?
Stop on 
Path? 
Stop at 
Prog Pt? 
Decel 
Rate 
Notes 
J/ 
Motor Yes  –- 
No Ixx19-
21 
 
C.S. 
Yes 
No 
No 
Ixx15 
No easy restart 
<CTRL-A> 
Global 
Yes 
No 
No 
Ixx15 
No easy restart 
C.S. 
No 
Yes 
Yes 
TA, TS  Finishes calculated moves 
<CTRL-Q> 
Global 
No 
Yes 
Yes 
TA, TS  Finishes calculated moves 
C.S. 
No 
Yes 
Yes 
TA, TS  End of currently executing 
move*, undoes blending 
C.S. 
Yes 
Yes 
No 
Isx95 
Similar to %0 
<CTRL-O> 
Global 
Yes 
Yes 
No 
Isx95 
Similar to %0 
C.S. Yes Yes  No Ixx17/ 
Isx95 
Acts as H command if 
outside of lookahead 
Motor Yes  No 
No 
 
Must stop program first 
<CTRL-K> 
Global Yes  No 
No 
 
Must stop program first 
Program Checksums 
Firmware Checksum 
Turbo PMAC continually computes the checksum of its internal program (firmware) as a background 
task.   Each time it has computed the checksum, it compares this value to a reference register in memory 
(obtainable with the CHECKSUM command) that has been manually entered with the correct value.  Turbo 
PMACs shipped from the factory are preloaded with the correct reference value for that firmware version 
at the factory.   
If Turbo PMAC detects a mismatch between its calculated checksum and the reference checksum, it sets 
global status bits (bits 12 and 13 of X:$000006 – accessible with the ??? command) and stops 
performing any checksum operations.  This leaves the calculated value frozen in the running checksum 
register X:$001080.  Turbo PMAC does take any other action in the event of a firmware checksum error; 
it is up to the host or a Turbo PMAC PLC program to decide what action to take. 
When a Turbo PMAC is upgraded to new firmware by replacement of the PROM IC in standard CPU 
sections or downloading of new firmware into the flash EEPROM IC in Option CPU sections, the 
reference checksum value will be updated automatically for the new firmware.   
User-Program Checksum 
Turbo PMAC continually computes the checksum of the fixed user program buffers as a background task.  
Each time it has computed the checksum, it compares this value to the checksum value that was computed 
the last time one of these buffers was closed, stored in X:$001090. 
If Turbo PMAC detects a mismatch between these two checksums, it sets a global status bit (bit 13 of 
X:$000006 – accessible with ???) and stops performing any program or firmware checksum operations 
(communications checksum is independent), freezing the running checksum value in X:$001080.  It does 
not shut down operation automatically.  It is up to the host or a Turbo PMAC PLC program to decide 
what action to take if there is a checksum error.