Function DISK_update

src/disk.cpp:4775–4863

}

void DISK_update (int tohpos)
{
	int dr;
	int cycles;

	if (disk_hpos < 0) {
		disk_hpos = -disk_hpos;
		return;
	}

	cycles = (tohpos << 8) - disk_hpos;
	if (cycles <= 0) {
		return;
	}

	disk_hpos += cycles;
	if (disk_hpos >= (maxhpos << 8)) {
		disk_hpos %= 1 << 8;
	}

	dskbytr_delay = false;

	for (dr = 0; dr < MAX_FLOPPY_DRIVES; dr++) {
		drive *drv = &floppy[dr];

		if (drv->motoroff || !drv->tracklen || !drv->trackspeed) {
			continue;
		}
		drv->floppybitcounter += cycles;
		if ((selected | disabled) & (1 << dr)) {
			drv->mfmpos += drv->floppybitcounter / drv->trackspeed;
			drv->mfmpos %= drv->tracklen;
			drv->floppybitcounter %= drv->trackspeed;
			continue;
		}
		if (drv->diskfile) {
			drive_fill_bigbuf(drv, side, 0);
		}
#ifdef FLOPPYBRIDGE
		if (drv->bridge) {
			drive_fill_bigbuf(drv, side, 0);
		}
#endif
		drv->mfmpos %= drv->tracklen;
	}
	int didaccess = 0;
	bool done_jitter = false;
	for (dr = 0; dr < MAX_FLOPPY_DRIVES; dr++) {
		drive *drv = &floppy[dr];
		if (drv->motoroff || !drv->trackspeed)
			continue;
		if ((selected | disabled) & (1 << dr))
			continue;
		if (!done_jitter) {
			update_jitter();
			done_jitter = true;
		}
		/* write dma and wordsync enabled: read until wordsync match found */