pTAL Reference Manual (H06.08+)

Built-In Routines
HP pTAL Reference Manual—523746-006
15-55
$INTERROGATEHIO
expression
is an expression whose value is an INT, INT(32), UNSIGNED(1-31), FIXED, REAL,
REAL(64), SGBADDR, SGWADDR, SGXBADDR, SGXWADDR, or EXTADDR
value.
If the data type of its argument is an INT(32) value greater than 32767 or less than
-32768, $INT_OV traps if overflow traps are enabled (see Section 13, Hardware
Indicators); otherwise, $INT_OV ignores the problem.
$INTERROGATEHIO
$INTERROGATEHIO stores cause and status information from a high-priority I/O
interrupt, which the operating system uses to reset the interrupt.
pTAL privileged procedure No
Can be executed only by privileged procedures No
Sets condition code No
Sets $CARRY No
Sets $OVERFLOW Yes
Example 15-45. Difference Between $INT and $INT_OV
INT i;
INT(32) j := 32767;
INT(32) k := 32768;
i := $INT(j); ! INT never sets overflow
IF $OVERFLOW THEN ... ! $OVERFLOW is false
i := $INT(k); ! INT never sets overflow
IF $OVERFLOW THEN ... ! $OVERFLOW is false
i := $INT_OV(j);
IF $OVERFLOW THEN ... ! $OVERFLOW is false
i := $INT_OV(k);
IF $OVERFLOW THEN ... ! $OVERFLOW is true
Note. The EpTAL compiler does not support this procedure.
( ,
,
$INTERROGATEHIO
,
select
rank-channel
ric-int-cause channel-status ,
) ;
VST643.vsd
rist-int-cause