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Installation manual
CNC 8055
CNC 8055i
7.
CONCEPTS
SOFT: V02.2X
Auxiliary M, S, T function transfer
7.8 Auxiliary M, S, T function transfer
Every time a block is executed in the CNC, information is passed to the PLC about the M, S, and
T functions which are active.
Auxiliary M function
The CNC uses logic outputs "MBCD1" thru "MBCD7" (R550 thru R556) to "tell" the PLC which M
functions it must execute. One function per logic output.
It also activates the general logic output "MSTROBE" to "tell" the PLC to start executing them.
Every time the CNC detects an M function, it analyzes the M function table to find out when to pass
it along to the PLC (either before or after the movement) and whether it must wait for the "AUXEND"
signal or not before resuming program execution.
If the programmed function is not defined in that table, it will be executed at the beginning of the
block and the CNC will wait for the "AUXEND" signal to resume program execution.
See "11.1 Auxiliary M, S, T functions" on page 476. See "12.7 General logic outputs" on page 512.
See "6.10 Tables" on page 285.
Example 1
Execution of a motion block containing 7 M functions 4 of which are executed before the axes move
(M51, M52, M53, M54) and 3 afterwards (M61, M62, M63).
1. It sends out to the PLC the 4 M functions programmed to be executed before the move
It sets logic outputs "MBCD1=51", "MBCD2=52" "MBCD3=53" "MBCD4=54" and it activates the
general logic output "MSTROBE to "tell" the PLC to go ahead with their execution.
Should any of them need the AUXEND activated, the CNC will "wait" for this signal to be activated
before going on to executing the rest of the block.
If none of them need the AUXEND signal activated, the CNC will maintain the "MSTROBE" signal
activated for a period of time set by the general machine parameter "MINAENDW (P30)". This
output stays active for the time indicated by general parameter MINAENDW (P30).
2. The programmed axis move will be executed.
3. It sends out to the PLC the 3 M functions programmed to be executed after the move.
It sets logic outputs "MBCD1=61", "MBCD2=62", "MBCD3=63" and it activates the general logic
output "MSTROBE to "tell" the PLC to go ahead with their execution.
Should any of them need the AUXEND activated, the CNC will "wait" for this signal to be activated
before going on to executing the rest of the block.
If none of them need the AUXEND signal activated, the CNC will maintain the "MSTROBE" signal
activated for a period of time set by the general machine parameter "MINAENDW (P30)". This
output stays active for the time indicated by general parameter MINAENDW (P30).
Example 2
Execution of a motionless block containing 7 M functions 4 of which are executed before the axes
move (M51, M52, M53, M54) and 3 afterwards (M61, M62, M63).
1. It sends out to the PLC the 4 M functions programmed to be executed before the move
It sets logic outputs "MBCD1=51", "MBCD2=52" "MBCD3=53" "MBCD4=54" and it activates the
general logic output "MSTROBE to "tell" the PLC to go ahead with their execution.
Should any of them need the AUXEND activated, the CNC will "wait" for this signal to be activated
before going on to executing the rest of the block.
If none of them need the AUXEND signal activated, the CNC will maintain the "MSTROBE" signal
activated for a period of time set by the general machine parameter "MINAENDW (P30)". This
output stays active for the time indicated by general parameter MINAENDW (P30).