80 lines
1.4 KiB
NASM
80 lines
1.4 KiB
NASM
jp Sysinit ; Startup vector: DO NOT MOVE! Must be the first instruction
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; Pat80 BIOS v0.01
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; @author: Daniele Verducci
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;
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; MEMORY MAP
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; ROM is at 0x0000
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; RAM is at 0x8000
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; SYSTEM VAR SPACE: 0x8000 - 0x8FFF (4kb)
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; DRIVERS VAR SPACE: 0x9000 - 0x9FFF (4kb)
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; APPLICATION VAR SPACE: 0xA000 - 0xFFFF (24kb)
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; I/O MAP
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; I/O 0 (0x00 - 0x1F) LCD (uses 0x00 and 0x01)
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; I/O 1 (0x20 - 0x3F)
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; I/O 2 (0x40 - 0x5F)
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; I/O 3 (0x60 - 0x7F)
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; I/O 4 (0x80 - 0x9F)
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; I/O 5 (0xA0 - 0xBF)
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; I/O 6 (0xC0 - 0xDF)
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; I/O 7 (0xE0 - 0xFF)
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; MEMORY CONFIGURATION
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SYS_VAR_SPACE: EQU 0x8000
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DRV_VAR_SPACE: EQU 0x9000
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APP_VAR_SPACE: EQU 0xA000
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; SYSTEM CONFIGURATION
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IO_0: EQU 0x00
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IO_1: EQU 0x20
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IO_2: EQU 0x40
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IO_3: EQU 0x60
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IO_4: EQU 0x80
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IO_5: EQU 0xA0
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IO_6: EQU 0xC0
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IO_7: EQU 0xE0
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;include 'drivers/hd44780.asm'
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;include 'drivers/keyboard.asm'
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include 'drivers/arduino_terminal.asm'
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include 'monitor.asm'
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; SYSTEM CALLS
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; User I/O
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; Prints string
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; @param BC Pointer to a null-terminated string first character
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Print:
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call Term_print
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ret
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; Writes a single character
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; @param A Value of character to print
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Printc:
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call Term_printc
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ret
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; Reads a single character
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; @return A The read character
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Readc:
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call Term_readc
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ret
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; Reads a line
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; @return BC The pointer to a null-terminated read string
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Readline:
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call Term_readline
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ret
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; System initialization
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Sysinit:
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; Start Monitor
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call Monitor_main
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halt
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