Chips

In order to get some of the software working in advance of the hardware being ready and due to the lack of debugging support on the hardware I'm tying to rejig a simulator to provide some support. After trying to get several to work I ended up with CHIPS  which allows me to play with the driving the CTC, which I'll need to get working to support the 50hz clock.
While none of the exiting ones is is perfect, the LC-80 emulator provides a good base, you can see them all at Tiny Emus.
I made a simple ROM which is below. To get it to work the source is assembled to chips-test\examples\roms\lc80_2k.bin then the  chips-test\examples\roms\lc80-roms.h deleted at the project make is run. I am using Visual Studio so I thin make the individual project and run it in debug mode. To check that it is working some bytes in the RAM as 0x2000 are updated.

CH0 equ 0h
CH1 equ 1h
CH2 equ 2h
CH3 equ 3h

IBASE   equ 200h
CTCIBASE equ 0h
SIOIBASE equ 8h


 .org 0000h
    di                        ;disable interrupts
    jr start

 .org 0066h
    jr NMIINT

start:
    ld sp, 23EAh

    IM  2
    LD  A,INTTBL/256
    LD  I,A
    EI

INI_CTC:
    ld A,00000000
    out (CH0),A

    ld A,10100101b
    out (CH0),A
    ld A,02h
    out (CH0),A

    ld A,10100111b
    out (CH1),A
    ld A,04h
    out (CH1),A


    ld A,10100111b
    out (CH2),A
    ld A,08h
    out (CH2),A


    ld A,10100111b
    out (CH3),A
    ld A,0FFh
    out (CH3),A

iloop:
    nop
    nop
    jr iloop

NMIINT:
    di
    push af
    ld A,(five)
    inc A
    ld (five),A
    pop af
    ei
    reti

CTC0INT:
;       ...     interrupt       routine
    di
    push af
    ld A,(one)
    inc A
    ld (one),A
    pop af
    ei
    RETI

CTC1INT:
;       ...     interrupt       routine
    di
    push af
    ld A,(two)
    inc A
    ld (two),A
    pop af
    ei
    RETI

CTC2INT:
;       ...     interrupt       routine
    di
    push af
    ld A,(three)
    inc A
    ld (three),A
    pop af
    ei
    RETI

CTC3INT:
;       ...     interrupt       routine
    di
    push af
    ld A,(four)
    inc A
    ld (four),A
    pop af
    ei
    RETI

SIO0INT:
;       ...     interrupt       routine
    di
    push af
    ld A,(six)
    inc A
    ld (six),A
    pop af
    ei
    RETI

 org 0200h

INTTBL:
    DW  CTC0INT
    DW  CTC1INT
    DW  CTC2INT
    DW  CTC3INT
 org     IBASE + SIOIBASE
    DW  SIO0INT


 org 07FFh
EndofROM   DB 0 ;Pad out to fill ROM

one equ 2000h
two equ 2001h
three equ 2002h
four equ 2003h
five equ 2004h
six equ 2005h

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