Siemens SINUMERIK 828D Function Manual page 577

Processing sequence
Sequence during activation through part program start
Initial state:
Channel: in the Reset-state
Mode: AUTO
AUTO + overstoring or MDA
TEACHIN
1. NC Start
2. Initialization sequence with evaluation of:
MD20112 $MC_START_MODE_MASK (Definition of the control default settings in case of NC START)
3. Implicit call of _N_PROG_EVENT_SPF as part program
4. Processing of the data part of the main program
5. Processing of the program part of the main program
Sequence during activation through part program end
Initial state:
Channel: in active status
Mode: AUTO
AUTO + overstoring or MDA
TEACHIN
1. Block with end of part program is changed
2. Control activates reset-sequence with evaluation of machine data:
MD $MC_RESET_MODE_MASK
$MC_GCODE_RESET_VALUES
$MC_GCODE_RESET_MODE
3. Implicit call of _N_PROG_EVENT_SPF as ASUB
4. Control activates reset-sequence with evaluation of machine data:
$MC_RESET_MODE_MASK
$MC_GCODE_RESET_VALUES
$MC_GCODE_RESET_MODE
⇒ The G code reset position continues to be set with machine data!
Basic Functions
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
K1: Mode group, channel, program operation, reset response
9.9 Program operation mode
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