Rockwell Automation 1770-KF2 Data Highway or Highway Plus Interface Module User Manual - Manual (Page 219)

Detailed Flowcharts
Appendix D
DĆ15
Figure D.17
TRANSMIT INTERRUPT Subroutine
11670
WAKEUP
TRANSMIT
INTERRUPT
INTERRUPT
RETURN
Resume Process
NOTE:
a Z80 S10.
This figure assumes the use of
NOTE: UART transmit interrupt must
be enabled and disabled without
affecting the current state of the
receive
enable flags.
and status interrupt
Sleeping at
TXWAIT
Figure D.18
SLEEP and WAKEUP Subroutines
11671
RETURN RETURN
Input
The address of a Sleep Variable.
Sleep Variables
Typically an address of a stack or
a process or context save area.
A process can suspend itself and
place its address in a Sleep
Variable.
Subsequently another process can
wake up the sleeping process by
referring to Sleep Variable. When
no process is sleeping at a Sleep
Variable, a WAKEUP has no effect.
Input
The address of a
SLEEP WAKEUP
•
•
•
•
•
An Implementation-
Dependent Routine to
Suspend Own Process
at a Sleep Variable Until
Another Process Wakes
This One Up
An Implementation-
Dependent Routine
to Wake Up the Process
at a Sleep Variable
if Any Is Sleeping There
Sleep Variable.