At entry, an SRB routine is in supervisor state, primary ASC mode,
enabled and unlocked unless you specified LLOCK=YES, in which case
the local lock is held. The general purpose registers contain the
following:
- Register
- Contents
- 0
- SRB address if SCHEDULE macro is used; zero if IEAMSCHD is used.
- 1
- Address of an area for passing user parameters from the scheduling
program to the SRB routine. (The user parameters are those specified
on the PARM parameter in IEAMSCHD or on the SRBPARM parameter in SCHEDULE.)
- 2
- If FRR=YES, 24-bit address of FRR parameter area; otherwise
used as a work area by the system
- 14
- Return address
- 15
- Entry point address
Other general purpose registers and all access registers are used
as work areas by the system.