pato-z80-home-computer/assembly/bios/main.asm
Daniele Verducci su MatissePenguin 3d4d5360c1 Sound working at very low cpu frequencies
2020-12-05 12:45:18 +01:00

88 lines
1.6 KiB
NASM

jp Sysinit ; Startup vector: DO NOT MOVE! Must be the first instruction
; Pat80 BIOS v0.01
; @author: Daniele Verducci
;
; MEMORY MAP
; ROM is at 0x0000
; RAM is at 0x8000
; SYSTEM VAR SPACE: 0x8000 - 0x8FFF (4kb)
; DRIVERS VAR SPACE: 0x9000 - 0x9FFF (4kb)
; APPLICATION VAR SPACE: 0xA000 - 0xFFFF (24kb)
; I/O MAP
; I/O 0 (0x00 - 0x1F) LCD (uses 0x00 and 0x01)
; I/O 1 (0x20 - 0x3F)
; I/O 2 (0x40 - 0x5F)
; I/O 3 (0x60 - 0x7F)
; I/O 4 (0x80 - 0x9F)
; I/O 5 (0xA0 - 0xBF)
; I/O 6 (0xC0 - 0xDF)
; I/O 7 (0xE0 - 0xFF)
; MEMORY CONFIGURATION
SYS_VAR_SPACE: EQU 0x8000
DRV_VAR_SPACE: EQU 0x9000
APP_SPACE: EQU 0xA000
; SYSTEM CONFIGURATION
IO_0: EQU 0x00
IO_1: EQU 0x20
IO_2: EQU 0x40
IO_3: EQU 0x60
IO_4: EQU 0x80
IO_5: EQU 0xA0
IO_6: EQU 0xC0
IO_7: EQU 0xE0
;include 'drivers/hd44780.asm'
;include 'drivers/keyboard.asm'
;include 'drivers/arduino_terminal.asm'
include 'drivers/sn76489.asm'
;include 'monitor.asm'
include 'libs/time.asm'
; SYSTEM CALLS
; User I/O
; ; Prints string
; ; @param BC Pointer to a null-terminated string first character
; Print:
; call Term_print
; ret
; ; Writes a single character
; ; @param A Value of character to print
; Printc:
; call Term_printc
; ret
; ; Reads a single character
; ; @return A The read character
; Readc:
; call Term_readc
; ret
; ; Reads a line
; ; @return BC The pointer to a null-terminated read string
; Readline:
; call Term_readline
; ret
; System initialization
Sysinit:
; Start Monitor
;call Monitor_main
call Snd_init
ld bc, 10
call Time_delay55
call Snd_beep
halt