HP Vectra Technical Reference Manual page 397

OUT
JMP
MOV
OUT
JMP
MOV
OUT
JMP
MOV
OUT
JMP
STI
OAOH,AL
$+2
AL,70H
OA1H,AL
$+2
AL,02H
OA 1H,AL
$+2
AL,01H
OA1H,AL
$+2
,. Interrupt Vector Base at 70H
,. Slave
10
number
,. 8086/88 Mode
" Reenable interrupts
The following example shows how an interrupt generated from the HP-Slave is serviced. This
provides an example of what commands to send the 8259 controllers to handle an
IRQ
request.
See Section 4 for more details.
,
" Interrupt handler example for handling an IRQ 16 which is an 8041
" keyboard controller service request:
,
INTERRUPT_HANDLER:
PUSH
IN
JMP
OR
OUT
JMP
MOV
OUT
JMP
AX
AL,7DH
$+2
AL,01H
7DH,AL
$+2
AL,20H
20H,AL
$+2
,. Save registers
,. Get enable mask from HP-Slave
" disable IRQ 16 interrupt
,. Send an EOI to master 8259
,. so that other interrupts can
" get thru
" 8041 Service processing here
IN AL,7DH
JMP
$+2
AND AL,OFEH
OUT
7DH,AL
JMP
$+2
MOV AL,60H
OUT
7CH,AL
JMP
$+2
POP AX
IRET
388
I/O Port Map
" Get enable mask from HP-Slave
" Enable IRQ 16 again
,. Send the HP-Slave a specific
,. EOI command.
" Restore registers