int_test.psm

来自「Xillinx 的8位MCU软核的源代码」· PSM 代码 · 共 26 行

             ;Interrupt example
             ;
             CONSTANT waveform_port, 02             ;bit0 will be data
             CONSTANT counter_port, 04
             CONSTANT pattern_10101010, AA
             NAMEREG s1A, interrupt_counter
             ; 
      start: LOAD interrupt_counter, 00             ;reset interrupt counter
             LOAD s02, pattern_10101010             ;initial output condition
             ENABLE INTERRUPT
             ;
 drive_wave: OUTPUT s02, waveform_port
             LOAD s00, 07                           ;delay size
       loop: SUB s00, 01                            ;delay loop
             JUMP NZ, loop
             XOR s02, FF                            ;toggle waveform
             JUMP drive_wave
             ; 
             ADDRESS 2B0
int_routine: ADD interrupt_counter, 01              ;increment counter
             OUTPUT interrupt_counter, counter_port
             RETURNI ENABLE
             ; 
             ADDRESS 3FF                            ;set interrupt vector
             JUMP int_routine