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2a55bfd375
We use zasm's ability to use labels in .equ directive. We didn't do it before because for a while, we were in between scas and zasm (scas was used in automated tests) so we needed to use the lowest common denominator: zasm doesn't have macros and scas can't use labels in .equ directives. This forced us to add this layer of indirection. But now that we are completely cut from scas' dependency, we can use this nice zasm's ability.
56 lines
915 B
NASM
56 lines
915 B
NASM
; 8K of onboard RAM
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.equ RAMSTART 0xc000
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; Memory register at the end of RAM. Must not overwrite
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.equ RAMEND 0xddd0
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jp init
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.fill 0x66-$
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retn
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.inc "err.h"
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.inc "core.asm"
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.inc "parse.asm"
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.inc "sms/kbd.asm"
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.equ KBD_RAMSTART RAMSTART
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.equ KBD_FETCHKC smskbdFetchKCB
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.inc "kbd.asm"
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.equ VDP_RAMSTART KBD_RAMEND
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.inc "sms/vdp.asm"
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.equ STDIO_RAMSTART VDP_RAMEND
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.equ STDIO_GETC kbdGetC
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.equ STDIO_PUTC vdpPutC
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.inc "stdio.asm"
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.equ SHELL_RAMSTART STDIO_RAMEND
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.equ SHELL_EXTRA_CMD_COUNT 0
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.inc "shell.asm"
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init:
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di
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im 1
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ld sp, RAMEND
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; Initialize the keyboard latch by "dummy reading" once. This ensures
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; that the adapter knows it can fill its '164.
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; Port B TH output, high
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ld a, 0b11110111
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out (0x3f), a
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nop
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; Port A/B reset
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ld a, 0xff
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out (0x3f), a
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call kbdInit
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call vdpInit
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call shellInit
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jp shellLoop
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.fill 0x7ff0-$
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.db "TMR SEGA", 0x00, 0x00, 0xfb, 0x68, 0x00, 0x00, 0x00, 0x4c
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