Specifications

Operating System Routines
IOC$ALOXBIMAP, IOC$ALOXBIMAPN
IOC$ALOXBIMAP, IOC$ALOXBIMAPN
Allocate a set of XBI+ map registers.
Module
[IO_ROUTINES]IOSUBNPAG
Input
Location Contents
R3 Number of XBI+ map registers to allocate
(IOC$ALOXBIMAPN only)
R5 Address of UCB
UCB$W_BCNT Transfer byte count (IOC$ALOXBIMAP only)
UCB$W_BOFF Byte offset in page (IOC$ALOXBIMAP only)
UCB$L_CRB Address of CRB
CRB$L_INTD+
VEC$L_ADP
Address of device ADP
ADP$L_BIMASTER Address of XBI+ adapter ADP
Output
Location Contents
R0 Status of operation
R1 Unpredictable
R2 Address of ADP
CRB$L_INTD+
VEC$W_XBINUMREG
Number of XBI+ map registers allocated
CRB$L_INTD+
VEC$W_MAPREG
Starting XBI+ map register number
Synchronization
Callers of IOC$ALOXBIMAP or IOC$ALOXBIMAPN must be executing at fork
IPL or above. No specific spinlock is required. Each routine returns control to its
caller at the caller’s IPL. The caller retains any spinlocks it held at the time of
the call.
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