Specifications

System Macros Invoked by Drivers
WFIKPCH, WFIRLCH
The suspended code thread is resumed by the occurrence of an interrupt signaling
the successful completion of a device operation. When an interrupt occurs, control
returns to the instruction following the macro. If a device timeout occurs before
an interrupt can be posted, the timeout handling routine specified in excpt is
called. In both instances, subsequent code can assume that only R3 and R4 have
been preserved across the suspension.
See the descriptions of the DEVICELOCK, IOFORK, and SETIPL macros for
examples of the use of the WFIKPCH macro.
2–109