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!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!
! Code for the test bench. This gets dumped and placed into testbench.v as byte
! definitions.
!

!
! Select controller defines
! 
selmain: equ    $00             ! offset of main control register
sel1msk: equ    $02             ! offset of select 1 mask
sel1cmp: equ    $03             ! offset of select 1 compare
sel2msk: equ    $04             ! offset of select 1 mask
sel2cmp: equ    $05             ! offset of select 1 compare
sel3msk: equ    $06             ! offset of select 1 mask
sel3cmp: equ    $07             ! offset of select 1 compare
sel4msk: equ    $08             ! offset of select 1 mask
sel4cmp: equ    $09             ! offset of select 1 compare
!
! bits
!
selenb:  equ    $01             ! enable select
selio:   equ    $02                     ! I/O address or memory

!
! Note: select 1 is ROM, 2, is RAM, 3 is interrupt controller
!

!
! Where to place ROM and RAM for this test
!
rombas: equ             $0000
rambas: equ             rombas+1024
!
! Interrupt controller defines
!
intbas: equ             $10
intmsk: equ             intbas+$00          ! mask
intsts: equ             intbas+$01          ! status
intact: equ             intbas+$02      ! active interrupt
intpol: equ             intbas+$03              ! polarity select
intedg: equ             intbas+$04              ! edge/level select
intvec: equ             intbas+$05              ! vector base page      

!
! Set up selectors
!

!
! ROM
!
        mvi             a,rombas shr 8  ! enable select 1 to 1kb at base
                out             sel1cmp
        mvi             a,($fc00 shr 8) or selenb
        out     sel1msk
!
! RAM
!
        mvi     a,rambas shr 8  ! enable select 2 to 1kb at base
        out     sel2cmp
        mvi     a,($fc00 shr 8) or selenb
        out     sel2msk
!
! ROM and RAM set up, exit bootstrap mode
!
        mvi     a,$00                   ! exit bootstrap mode 
        out     selmain
!
                lxi             sp,rambas+1024  ! set stack to top of ram
!
! Interrupt controller
!
                mvi             a,intbas                ! enable interrupt controller for 8 addresses           
                out             sel3cmp
                mvi             a,$f8 or selio or selenb
                out             sel3msk
!
! Set up interrupt controller for test
!
                mvi             a,$0100 shr 8   ! vector to page 1
                out             intvec
                mvi             a,$01                   ! enable interrupt 0
                out             intact
!
! Interrupt here
!
                nop
                nop
                hlt                                             ! and stop
!
! Locate to page 1
!
                alignp  256
                ret                                             ! return from interrupt