93 lines
1.8 KiB
NASM
93 lines
1.8 KiB
NASM
.include "extern_symbols.s" ;include monitor symbols.
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START_ADDR .EQU 0x8000
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org START_ADDR
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com_header:
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jp com_prg
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db 0x00
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dw 0x00, 0x00, 0x00 ;always 0
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dw [START_ADDR] ;start addr
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dw [_eof] ;end of file
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dw [_eof - START_ADDR] ;length
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dc 48,0x00
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com_prg:
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;shadow rom
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call PRINTINLINE
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db 10,13,"Shadowing ROM @ 0x0000-0x3FFF ...",10,13,0
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ld a,0x01 ;set bit1 to switch to ram
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out (0x00),a ;store to bank select register
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ld hl,[prg_start]
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ld de,0
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ld bc,[prg_end-prg_start]
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ldir
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jp 0x0000
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prg_start:
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phase 0x0000
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BASRST_00: ;Hardware Restart
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jp CSTART
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defs 5
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;org 0x0008
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BASRST_08 ;Print Char
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jp _BASRST_08
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defs 5
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;org 0x0010
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BASRST_10 ;receive char
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jp _BASRST_10
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defs 5
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;org 0x0018
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BASRST_18 ;Buffer length
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jp _BASRST_18
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defs 5
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;org 0x0044
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_BASRST_08:
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out (CS_SIO_A_D),a
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_wait:
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ld a,1
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out (CS_SIO_A_C),A
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in A,(CS_SIO_A_C) ;read RRx
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bit 0,A
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jr z,_wait
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ret
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_BASRST_10:
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;RTS ON
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ld a,005h ;write into WR0: select WR5
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out (CS_SIO_A_C),A
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ld a,0EAh ;DTR active, TX 8bit, BREAK off, TX on, RTS active
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out (CS_SIO_A_C),A
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nop
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;read if avail
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xor a ; a = 0
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out (CS_SIO_A_C), a ; select reg 0
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in a, (CS_SIO_A_C) ; read reg 0
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and 1 ; mask D0 (recieve char available)
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;RTS OFF
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push af
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ld a,005h ;write into WR0: select WR5
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out (CS_SIO_A_C),A
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ld a,068h ;DTR inactive, TX 8bit, BREAK off, TX on, RTS inactive
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out (CS_SIO_A_C),A
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pop af
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ret Z ; return 0 if no char
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;read data
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in a, (CS_SIO_A_D) ; read char if avail
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ret ; return
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_BASRST_18:
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ld a,0
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ret
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BASSTART:
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.include "basic.s"
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_WORKSPACE:
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dephase
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prg_end:
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_eof: |