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Most of register fiddling routines (which is now the only thing contained in care.asm) are used by almost all userspace apps, often in inner loops. That makes the penalty of using jump tables for those a bit too high. Moreover, it burdens jump tables needlessly. Because this unit is very small (now that string routines are out), it makes sense to always include it in binaries.
58 lines
945 B
NASM
58 lines
945 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 "ascii.h"
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.inc "core.asm"
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.inc "str.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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