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[/] [light8080/] [trunk/] [sw/] [tb/] [tb1/] [tb1.asm] - Blame information for rev 74

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1 74 ja_rd
;*******************************************************************************
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; tb1.asm -- light8080 core test bench 1: interrupt & halt test
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;*******************************************************************************
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; Should be used with test bench template vhdl\test\tb_template.vhdl
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; Assembler format compatible with TASM for DOS and Linux.
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;*******************************************************************************
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; This program will test a few different interrupt vectors and the interrupt
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; enable/disable flag, but not exhaustively.
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; Besides, it will not test long intr assertions (more than 1 cycle).
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;*******************************************************************************
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; DS pseudo-directive; reserve space in bytes, without initializing it
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#define ds(n)    \.org $+n
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; OUTing some value here will trigger intr in the n-th cycle from the end of
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; the 'out' instruction. For example, writing a 0 will trigger intr in the 1st
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; cycle of the following instruction, and so on.
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intr_trigger: .equ 11h
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; The value OUTput to this address will be used as the 'interrupt source' when
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; the intr line is asserted. In the inta acknowledge cycle, the simulated
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; interrupt logic will feed the CPU the instruction at memory address
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; 40h+source*4. See vhdl\test\tb_template.vhdl for details.
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intr_source:  .equ 10h
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; The value OUTput to this port is the number of cycles the intr signal will
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; remain high after being asserted. By default this is 1 cycle.
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intr_width:   .equ 12h
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; OUTing something here will stop the simulation. A 0x055 will signal a
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; success, a 0x0aa a failure.
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test_outcome: .equ 20h
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;*******************************************************************************
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        .org    0H
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        jmp     start           ; skip the rst address area
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        ; used to test that RST works
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        .org    20H
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        adi     1H
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        ei
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        ret
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        ; used to test the RST instruction as intr vector
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        .org    28H
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        inr     a
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        ei
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        ret
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        ;***** simulated interrupt vectors in area 0040h-005fh *****************
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        .org    40h+(0*4)       ; simulated interrupt vector 0
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        inr     a
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        .org    40h+(1*4)       ; simulated interrupt vector 1
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        rst     5
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        .org    40h+(2*4)       ; simulated interrupt vector 2
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        inx     h
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        .org    40h+(3*4)       ; simulated interrupt vector 3
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        mvi     a,42h
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        .org    40h+(4*4)       ; simulated interrupt vector 4
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        lxi     h,1234h
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        .org    40h+(5*4)       ; simulated interrupt vector 5
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        jmp     test_jump
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        .org    40h+(6*4)       ; simulated interrupt vector 6
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        call    test_call
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        .org    40h+(7*4)       ; simulated interrupt vector 7
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        call    shouldnt_trigger
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        ;***** program entry point *********************************************
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start:  .org    60H
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        lxi     sp,stack
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        ; first of all, make sure the RST instruction works, we have a valid
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        ; simulated stack, etc.
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        mvi     a,13h
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        rst     4               ; this should add 1 to ACC
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        cpi     14h
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        jnz     fail
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        ; now we'll try a few different interrupt vectors (single byte and
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        ; multi-byte). Since interrupts are disabled upon acknowledge, we have
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        ; to reenable them after every test.
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        ; try single-byte interrupt vector: INR A
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        mvi     a,0
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        out     intr_source
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        ei
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        mvi     a,014h
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        out     intr_trigger
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        mvi     a,027h
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        nop                       ; the interrupt will hit in this nop area
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        nop
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        nop
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        nop
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        cpi     028h
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        jnz     fail
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        ; another single-byte vector: RST 5
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        mvi     a,1
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        out     intr_source
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        ei
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        mvi     a,014h
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        out     intr_trigger      ; the interrupt vector will do a rst 5, and
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        mvi     a,020h            ; the rst routine will add 1 to the ACC
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        nop                       ; and reenable interrupts
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        nop
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        nop
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        nop
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        cpi     021h
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        jnz     fail
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        ; another single-byte code: INX H
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        lxi     h,13ffh
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        mvi     a,2
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        out     intr_source
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        ei
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        mvi     a,4
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        out     intr_trigger
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        nop
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        nop
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        mov     a,l
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        cpi     0H
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        jnz     fail
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        mov     a,h
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        cpi     14h
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        jnz     fail
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        ; a two-byte instruction: mvi a, 42h
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        mvi     a,3
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        out     intr_source
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        ei
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        mvi     a,4
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        out     intr_trigger
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        nop
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        nop
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        cpi     42h
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        jnz     fail
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        ; a three-byte instruction: lxi h,1234h
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        mvi     a,4
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        out     intr_source
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        ei
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        mvi     a,4
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        out     intr_trigger
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        nop
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        nop
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        mov     a,h
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        cpi     12h
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        jnz     fail
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        mov     a,l
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        cpi     34h
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        jnz     fail
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        ; a 3-byte jump: jmp test_jump
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        ; if this fails, the test will probably derail
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        mvi     a,5
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        out     intr_source
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        ei
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        mvi     a,4
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        out     intr_trigger
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        nop
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        nop
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comeback:
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        cpi     79h
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        jnz     fail
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        ; a 3-byte call: call test_call
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        ; if this fails, the test will probably derail
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        mvi     a,6
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        out     intr_source
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        ei
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        mvi     a,4
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        out     intr_trigger
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        inr     a
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        ; the interrupt will come back here, hopefully
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        nop
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        cpi     05h
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        jnz     fail
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        mov     a,b
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        cpi     19h
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        jnz     fail
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        ; now, with interrupts disabled, make sure interrupts are ignored
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        di
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        mvi     a,07h           ; source 7 catches any unwanted interrupts
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        out     intr_source
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        mvi     a,04h
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        out     intr_trigger
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        nop
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        nop
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        nop
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        ; Ok. So far we have tested only 1-cycle intr assertions. Now we'll
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        ; see what happens when we leave intr asserted for a long time (as would
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        ; happen intr was used for single-step debugging, for instance)
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        ; try single-byte interrupt vector (INR A)
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        mvi     a, 80
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        out     intr_width
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        mvi     a,1
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        out     intr_source
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        ei
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        mvi     a,014h
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        out     intr_trigger
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        mvi     a,027h
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        nop                       ; the interrupts will hit in this nop area
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        nop
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        inr     a
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        nop
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        nop
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        inr     a
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        nop
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        nop
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        nop
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        nop
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        nop
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        cpi     02bh
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        jnz     fail
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        ; finished, run into the success outcome code
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success:
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        mvi     a,55h
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        out     test_outcome
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        hlt
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fail:   mvi     a,0aah
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        out     test_outcome
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        hlt
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test_jump:
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        mvi     a,79h
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        jmp     comeback
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test_call:
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        mvi     b,19h
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        ret
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; called when an interrupt has been acknowledged that shouldn't have
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shouldnt_trigger:
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        jmp     fail
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        ; data space
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        ds(64)
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stack:  ds(2)
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        .end
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