print more chipselect info

[32620_extract] / extract.c

/* Extractor for Geraet 32620 ROM files
 *
 * Copyright (c) 2020 Michael Gernoth <michael@gernoth.net>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */
#include <errno.h>
#include <inttypes.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>

int main(int argc, char **argv)
{
	uint8_t header[64];
	uint32_t adrs[(64/3)+1] = { 0 };
	uint8_t cs2 = 0;
	int fd;
	int r;
	int i;
	int count = 0;

	if (argc != 3) {
		fprintf(stderr, "Syntax: %s in.bin prefix\n", argv[0]);
		exit(EXIT_FAILURE);
	}

	fd = open(argv[1], O_RDONLY);
	if (fd == -1) {
		perror("Can't open ROM");
		exit(EXIT_FAILURE);
	}

	r = read(fd, header, sizeof(header));
	if (r != sizeof(header)) {
		perror("Can't read header");
		exit(EXIT_FAILURE);
	}

	/*
	 * From: https://blog.ardy.io/2020/8/geraet-32620/
	 *
	 * 00000000 01000000 01000011 10110111 01001010 01000011 11000011 01011000
	 * ^^^^^^^^ ^^^^^^^^ ^^^^^^^^|                          |
	 * LIIIIIII LIILIIII LIIIILII
	 *        I   I    I     |  +-- Amplification (Default: 3)
	 *        I   I    I     +----- Chip/Module Select lines/EOF?
	 *        I   I    +----------- Address (HI Byte)
	 *        I   +---------------- Chip Select lines A15, A14, A13
	 *        +-------------------- Address (LO Byte)
	 */ 
	for (i = 0; i < 62; i+=3) {
		uint8_t hi, lo, amp, cs;
		uint32_t adr;

		lo = header[i];
		hi = header[i+1] & 0x1f;

		//!EOF ?!
		if ((header[i+2] & 0xf8) != 0xf8)
			cs2 = (header[i+2] & 0xf8) >> 3;

		if (cs2 & 0x08) {
			cs = ((header[i+1] & 0xe0) >> 5) - 2;
		} else {
			cs = (((header[i+1] & 0xe0) >> 5) | (1 << 3)) - 4;
		}

		amp = header[i+2] & 0x3;

		adr = ((hi << 8) | lo) + (cs * 8192);
		if (adr == 0)
			adr += sizeof(header);

		printf("%02d. hi: 0x%02x, lo: 0x%02x, cs: 0x%02x, cs2: 0x%02x -> chip: 0x%02x, adr: 0x%04x; amp: 0x%02x\n",
		       i/3, hi, lo,
		       ((header[i+1] & 0xe0) >> 5),
		       ((header[i+2] & 0xf8) >> 3),
		       cs, adr, amp);

		adrs[i/3] = adr;
		if ((header[i+2] & 0xf8) == 0xf8)
			break;

		count++;
	}

	for (i = 0; i < count; i++) {
		uint8_t buf[65536];
		uint32_t len;
		char file[32];
		int fd_out;

		lseek(fd, adrs[i], SEEK_SET);

		len = adrs[i+1] - adrs[i];

		if (!len)
			break;

		printf("%02d. Length: %d\n", i, len);
		memset(file, 0, sizeof(file));
		snprintf(file, sizeof(file)-1, "%s-%02d.raw", argv[2], i);

		fd_out = open(file, O_WRONLY|O_CREAT|O_TRUNC, 0644);
		if (fd_out == -1) {
			perror("Can't open out");
			exit(EXIT_FAILURE);
		}

		r = read(fd, buf, len);
		if (r != len) {
			perror("Can't read content");
			exit(EXIT_FAILURE);
		}

		r = write(fd_out, buf, len);
		if (r != len) {
			perror("Can't write content");
			exit(EXIT_FAILURE);
		}

		close(fd_out);

	}

	close(fd);

	return EXIT_SUCCESS;
}