Function drive_write_pcdos

src/disk.cpp:2725–2828

}

static int drive_write_pcdos (drive *drv, struct zfile *zf, bool count)
{
	int i;
	int drvsec = drv->num_secs;
	int fwlen = FLOPPY_WRITE_LEN * drv->ddhd;
	int length = 2 * fwlen;
	uae_u16 *mbuf = drv->bigmfmbuf;
	uae_u16 *mend = mbuf + length;
	int secwritten = 0, seccnt = 0;
	int shift = 0, sector = -1;
	int sectable[24];
	uae_u8 secbuf[3 + 1 + 512];
	uae_u8 mark;
	uae_u16 crc;

	memset (sectable, 0, sizeof sectable);
	memcpy (mbuf + fwlen, mbuf, fwlen * sizeof (uae_u16));
	mend -= 518;
	secbuf[0] = secbuf[1] = secbuf[2] = 0xa1;
	secbuf[3] = 0xfb;

	while (seccnt < drvsec) {
		int mfmcount;

		mfmcount = 0;
		while (getmfmword (mbuf, shift) != 0x4489) {
			mfmcount++;
			if (mbuf >= mend)
				return -1;
			shift++;
			if (shift == 16) {
				shift = 0;
				mbuf++;
			}
			if (sector >= 0 && mfmcount / 16 >= 43)
				sector = -1;
		}

		mfmcount = 0;
		while (getmfmword (mbuf, shift) == 0x4489) {
			mfmcount++;
			if (mbuf >= mend)
				return -1;
			mbuf++;
		}
		if (mfmcount < 3) // ignore if less than 3 sync markers
			continue;

		mark = mfmdecode(&mbuf, shift);
		if (mark == 0xfe) {
			uae_u8 tmp[8];
			uae_u8 cyl, head, size;

			cyl = mfmdecode (&mbuf, shift);
			head = mfmdecode (&mbuf, shift);
			sector = mfmdecode (&mbuf, shift);
			size = mfmdecode (&mbuf, shift);
			crc = (mfmdecode (&mbuf, shift) << 8) | mfmdecode (&mbuf, shift);