sigh. i dont know

.gitignore

@@ -1,2 +1,2 @@
-*.COM
+*.bin
-*.BIN
+scripts/

.gitmodules

@@ -1,3 +0,0 @@
-[submodule "8080"]
-	path = HOST/8080
-	url = https://github.com/superzazu/8080.git

HOST/8080

@@ -1 +0,0 @@
-Subproject commit ec5d2bd99cbf9286224675e5e46849277479ef82

HOST/em8080.c

@@ -1,149 +0,0 @@
-// This file uses the 8080 emulator to run the test suite (roms in cpu_tests
-// directory). It uses a simple array as memory.
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <time.h>
-#include "8080/i8080.h"
-
-// memory callbacks
-#define MEMORY_SIZE 0x10000
-static uint8_t* memory = NULL;
-static bool test_finished = 0;
-
-static uint8_t rb(void* userdata, const uint16_t addr) {
-    return memory[addr];
-}
-
-static void wb(void* userdata, const uint16_t addr, const uint8_t val) {
-    memory[addr] = val;
-}
-
-uint16_t dma_addr;
-uint8_t cur_disk = 'Z'-'A';
-char filename[16];
-
-void filename_from_fcb(void* userdata, uint16_t addr) {
-  i8080* const c = (i8080*) userdata;
-  memset(&filename, 0, sizeof(filename));
-  char* ptr = filename;
-  while(rb(c, addr) != '.' && rb(c, addr) > ' ') {
-    *ptr++ = rb(c, addr++);
-  }
-  if (rb(c, addr) == '.') {
-    addr++;
-    while(rb(c, addr) > ' ') {
-      *ptr++ = rb(c, addr++);
-    }
-  }
-}
-
-void filename_to_fcb(void* userdata, uint16_t addr) {
-
-}
-
-static uint8_t port_in(void* userdata, uint8_t port) {
-  i8080* const c = (i8080*) userdata;
-  uint16_t de = (c->d << 8) | c->e;
-
-  switch(c->c) {
-  case 2:
-    printf("%c", c->e);
-    break;
-  case 9:
-    do {
-      printf("%c", rb(c, de++));
-    } while(rb(c, de) != '$');
-    break;
-  case 15:
-    filename_from_fcb(userdata, de);
-    printf("filename: %s\n", filename);
-    exit(1);
-    break;
-  case 25:
-    c->a = cur_disk;
-    break;
-  case 26:
-    dma_addr = (c->d << 8) | c->e;
-    break;
-  default:
-    i8080_debug_output(c);
-    fprintf(stderr, "fatal: unknown syscall C=%02Xh (%d)\n", c->c, c->c);
-    exit(255);
-  }
-
-  return c->a;
-}
-
-static int load_file(const char* filename, uint16_t addr) {
-    FILE* f = fopen(filename, "rb");
-    if (f == NULL) {
-        fprintf(stderr, "error: can't open file '%s'.\n", filename);
-        return 1;
-    }
-
-    // file size check:
-    fseek(f, 0, SEEK_END);
-    size_t file_size = ftell(f);
-    rewind(f);
-
-    if (file_size + addr >= MEMORY_SIZE) {
-        fprintf(stderr, "error: file %s can't fit in memory.\n", filename);
-        return 1;
-    }
-
-    // copying the bytes in memory:
-    size_t result = fread(&memory[addr], sizeof(uint8_t), file_size, f);
-    if (result != file_size) {
-        fprintf(stderr, "error: while reading file '%s'\n", filename);
-        return 1;
-    }
-
-    fclose(f);
-    return 0;
-}
-
-int main(int argc, char** argv) {
-    memory = malloc(MEMORY_SIZE);
-    if (memory == NULL) {
-        return 255;
-    }
-
-    argc--;
-    if (!argc) {
-      fprintf(stderr, "No filename given\n");
-      return 255;
-    }
-    argv++;
-
-    i8080 cpu;
-    i8080_init(&cpu);
-    cpu.userdata = &cpu;
-    cpu.read_byte = rb;
-    cpu.write_byte = wb;
-    cpu.port_in = port_in;
-    memset(memory, 0, MEMORY_SIZE);
-
-    if (load_file(argv[0], 0x100) != 0) {
-        return 255;
-    }
-
-    cpu.pc = 0x100;
-    // inject "hlt" at 0x0000
-    memory[0x0000] = 0x76;
-
-    // inject "in a,0" at 0x0005 (cpm syscall)
-    memory[0x0005] = 0xDB;
-    memory[0x0006] = 0x00;
-    memory[0x0007] = 0xC9;
-
-    while (!cpu.halted) {
-//        i8080_debug_output(&cpu);
-        i8080_step(&cpu);
-    }
-
-    free(memory);
-
-    return cpu.a;
-}

Makefile

@@ -1,17 +1,14 @@
-DISTFILES = $(PROGRAMS)
+.PHONY: default
 
-.PHONY: default bootstrap clean qemu-rom qemu-floppy
+cp437.bin: src/cp437.bmp scripts/bmp2font
+	scripts/bmp2font $< $@
 
-default: fdimage.img
+vga11.bin: src/vga11.asm cp437.bin
+	nasm -o $@ $<
 
-MAC.COM:
+scripts/%: src/scripts/%.c
-	wget -N http://www.cpm.z80.de/download/mac-b.zip
+	mkdir -p scripts
-	unzip mac-b.zip
+	gcc -o $@ $<
-
-CP437.BIN: CP437.BMP HOST/bmp2font
-	HOST/bmp2font $< $@
-
-HOST/em8080: HOST/8080/i8080.o HOST/em8080.o
 
 clean:
-	rm -f *.COM *.BIN HOST/bmp2font HOST/em8080 HOST/*.o
+	rm -f *.bin scripts/*

README.md

@@ -1,45 +0,0 @@
-## Components
-
-The BIOS is in the uppermost 2K of the memory area - it provides basic character and disk I/O functions.
-It it expected to stay static and not be unloaded by the user program.
-The BIOS may hook into interrupts if necessary to provide its functionality.
-Depending on your hardware, a different BIOS binary may be used.
-
-The BDOS is in the 2K below the BIOS, it provides a filesystem driver to work atop of the BIOS.
-It is agnostic to the underlaying hardware configuration, but different depending on the instruction set.
-A user program might overwrite memory up to the end of the BDOS.
-Upon program exit, the BIOS will reload the BDOS from disk.
-
-## Memory Layout
-
-On a 8080, there are no segments, the addresses are as displayed.
-
-On on the 8086, a single segment with a value of 0x0100 is assumed.
-This implies that the first 4k of memory are not used.
-
-The BIOS and BDOS may be recompiled for starting at a lower address, in this case,
-the minimum memory requirement may be less than 64k.
-
-|Start |Size     |Function|
-|------|---------|--------|
-|0xF800|2k       |BIOS / hw drivers|
-|0xF000|2k       |BDOS|
-|...   |...      |BDOS data area, disk deblocking buffers|
-|SP    |var      |Stack, growing down|
-|...   |...      |Free memory|
-|...   |var      |Heap, growing up|
-|0x0100|var      |Transient Program Area|
-|0x0080|128 bytes|Command line and disk buffer|
-|0x006C|20 bytes |Pre-filled FCB 2|
-|0x005C|16 bytes |Pre-filled FCB 1|
-|0x0008|84 bytes |BIOS data area, specific to BIOS implementation|
-|0x0005|3 bytes  |Jump code for BDOS|
-|0x0004|1 byte   |default drive for BDOS|
-|0x0003|1 byte   |may be used as iobyte by BIOS|
-|0x0000|3 bytes  |Jump to BIOS warm boot entry point / program exit|
-
-## Application program interface
-
-It is using the `call 5` convention with CP/M compatible syscall numbers.
-
-File I/O is done via FCB blocks.

src/vga11.asm

@@ -0,0 +1,99 @@
+org 0x7C00
+
+cols: equ 80
+rows: equ 30
+
+main:
+  mov ax, cs
+  mov ds, ax
+  mov es, ax
+  mov ss, ax
+  xor sp, sp
+
+  mov ah, 0x42
+  mov si, dap
+  int 0x13
+
+  mov ax, 0x0011
+  int 0x10
+
+  mov di, txtbuf
+.loop:
+  call sync
+  xor ax, ax
+  int 0x16
+  stosb
+  jmp .loop
+
+hlt:
+  hlt
+  jmp hlt
+
+sync:
+  push ax
+  push si
+  push di
+  push es
+  mov si, txtbuf
+  mov ax, 0xA000
+  mov es, ax
+  mov di, 0
+
+  mov bx, font
+  mov cx, rows
+.loop:
+  call charline
+  loop .loop
+
+  pop es
+  pop di
+  pop si
+  pop ax
+  ret
+
+charline:
+  push bx
+  push cx
+  mov cx, 8
+.loop:
+  call scanline
+  call scanline
+  inc bh
+  loop .loop
+  add si, cols
+  pop cx
+  pop bx
+  ret
+
+scanline:
+  push si
+  push cx
+  mov cx, cols
+.loop:
+  lodsb
+  mov bl, al
+  mov al, [bx]
+  stosb
+  loop .loop
+  pop cx
+  pop si
+  ret
+
+dap:
+  db 0x10
+  db 1
+  dw 20
+  dw font, 0
+  dq 1
+
+times (510 - ($-$$)) nop
+
+dw 0xAA55
+
+font:
+  incbin "cp437.bin"
+
+txtbuf:
+  times (rows * cols) db 0
+
+end: