Rockwell Automation 1775-KA PLC-3 Communication Adapter Module User Manual - Manual (Page 226)

Detailed Flowcharts
Appendix D
DĆ16
Figure D.18
TRANSMIT INTERRUPT Subroutine
10088-I
WAKEUP
TRANSMIT
INTERRUPT
INTERRUPT
RETURN
Resume Process
Sleeping At
TXWAIT
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
flags.
and status interruptenable
Figure D.19
SLEEP and WAKEUP Subroutines
10089-I
RETURN
RETURN
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
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 Variable.
SLEEP WAKEUP
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