Template
RuiFPB
3801459e1e
- DATA and RODATA segments added to computer.cfg - RAM memory configuration now starts at to not overwrite the cpu stack - hardware.inc added to handle hardware related constants - constants removed from via.s - constants removed from serial.s - serial_delay from serial.s is now dynamic, dependant on CPU_HZ and baud rate - serial_baud_* functions added to setup 19200 and 9600 baud - mem_copy.s added. data copy functions are to be implemented here - copy_data (mem_copy.s) implemented to copy the DATA segment from ROM to RAM - propper system setup in main.s - Makefile now generates a .map file with the memory map information
72 lines
1.7 KiB
ArmAsm
72 lines
1.7 KiB
ArmAsm
.import serial_setup, serial_print_char, serial_recv_char
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.import copy_data
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; ---------------
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; ZP
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; ---------------
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.zeropage
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; Zero-page variables ($0000 - $00ff)
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; ---------------
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; BSS
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; ---------------
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.bss
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; RAM variables ($0200 - $7fff)
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; ---------------
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; DATA
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.data
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; Initialized RAM variables ($0200 - $7fff)
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; ---------------
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; CODE
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.code
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; Actual program code ($c000 - $fff9)
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reset: ; Program starts here
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; System setup
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sei ; disable interrupts while setting things up
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cld ; clear BCD mode flag (undefined on NMOS 6502, auto cleared on 65C02)
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ldx #$ff
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txs ; Reset stack pointer
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jsr copy_data ; copy data variables from ROM to RAM
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jsr serial_setup ; setup serial interface (65C51N). 19200 baud set as default
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print_hello_world:
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ldx #0
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@loop:
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lda str_hello_world,x ; get char
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beq @end ; IF char is 0, done
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jsr serial_print_char ; send char to console
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inx ; increment x (next char)
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jmp @loop
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@end:
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jmp @end
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irq_handler: ; IRQ Handler
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rti ; Do nothing
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nmi_handler: ; NMI handler
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rti ; Do nothing
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; ---------------
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; RODATA
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; ---------------
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.rodata
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; Constants
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str_hello_world: .asciiz "Hello, World!"
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; ---------------
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; VECTORS
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.segment "VECTORS"
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; NMI, RESET and IRQ vectors
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.word nmi_handler
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.word reset
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.word irq_handler
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