National Instruments PC-TIO-10 User Manual page 48

Chapter 4
Also,
isr_handler()
issuing the end-of-interrupt command. If interrupts are still active when the end-of-interrupt
command is issued, program operation usually becomes unstable and is likely to lock up the
computer.
; assemble this file with the following command:
; masm /MX filename;
; /MX preserves case sensitivity
;
;
; function prototypes:
;
; void install_isr(int level, isr_block_type far * isr_block);
;
; on input, level indicates the interrupt level that is to be modified
; on input, isr_block points to the data structure that will be used by
; the isr_handler function
;
; void isr_handler(void);
;
; the isr_handler() function will never be called from C.....
;
; void remove_isr(void);
;
public _install_isr, _isr_handler, _remove_isr
_DATA segment word public 'DATA'
; declarations
ackm equ 00020h
acks equ 000a0h
eoi equ 00020h
maskm equ 00021h
masks equ 000a1h
int_addr dd 0
int_mask dw 0
isrb_addr dd 0
slave_ack db 0
vect_num db 0
_DATA ends
_TEXT segment word public 'CODE'
assume cs:_TEXT, ss:_TEXT, ds:_DATA
; install_isr
;
; bp reg at [bp+0]
; ret addr ofs at [bp+2]
; ret addr seg at [bp+4]
; level at [bp+6]
; isr_block ofs at [bp+8]
; isr_block seg at [bp+10]
;
© National Instruments Corporation
should check, service, and clear both Port A and Port B interrupts before
4-15
Programming
PC-TIO-10 User Manual