GDSX (Extended General Device Support) Manual

DEVICE^HANDLER Example, Design
Extended General Device Support (GDSX) Manual—529931-001
5-6
Basic Structure of DEVICE^HANDLER Code
Basic Structure of DEVICE^HANDLER Code
A DEVICE^HANDLER task starts when TSCODE calls the DEVICE^HANDLER
procedure. After any necessary initialization processing, the task runs in a continuous
loop, reading from the pseudo-$RECEIVE file and sending output to and receiving
input from its device, never doing a RETURN to TSCODE. This structure is shown in
Figure 5-3.
Figure 5-3. DEVICE^HANDLER Program Structure
INIT
PROCESSING
WHILE (1)
DO
^READUPDATE
PSEUDO-$RCV
DECODE
REQUEST
WT WT^RD RD
CTRL
SET^MD
PROCESS REQUEST
DATA
^WT
TERM
^WT^RD
TERM
^RD
TERM
PROCESS
CTRL
PROCESS
SET^MD
PROCESS REPLY
DATA
^REPLY
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