Assume track uses 4us bit cell timing if track total length is less than 66% of nomin...

diff --git a/disk.cpp b/disk.cpp
index b6ccd49a62f1e800ce9968ae582da314d269c714..888ea3db84d401e016c17f9a8b4b8b356bce4f82 100644 (file)
--- a/disk.cpp
+++ b/disk.cpp
@@ -562,11 +562,20 @@ static int get_floppy_speed (void)
        return m;
 }
 
-static int get_floppy_speed2 (drive *drv)
+static int get_floppy_speed_from_image(drive *drv)
 {
-       int m = get_floppy_speed () * drv->tracklen / (2 * 8 * FLOPPY_WRITE_LEN * drv->ddhd);
+       int l, m;
+       
+       l = drv->tracklen;
+       m = get_floppy_speed () * l / (2 * 8 * FLOPPY_WRITE_LEN * drv->ddhd);
+
+       // 4us track?
+       if (l < (FLOPPY_WRITE_LEN_PAL * 8) * 4 / 6)
+               m *= 2;
+
        if (m <= 0)
                m = 1;
+
        return m;
 }
 
@@ -2048,7 +2057,7 @@ static void drive_fill_bigbuf (drive * drv, int force)
                memset (drv->bigmfmbuf, 0, FLOPPY_WRITE_LEN * 2 * drv->ddhd);
        }
 
-       drv->trackspeed = get_floppy_speed2 (drv);
+       drv->trackspeed = get_floppy_speed_from_image(drv);
        updatemfmpos (drv);
 }
 
@@ -3270,7 +3279,7 @@ static void fetchnextrevolution (drive *drv)
 {
        if (drv->revolution_check)
                return;
-       drv->trackspeed = get_floppy_speed2 (drv);
+       drv->trackspeed = get_floppy_speed_from_image(drv);
 #if REVOLUTION_DEBUG
        if (1 || drv->mfmpos != 0) {
                write_log (_T("REVOLUTION: DMA=%d %d %d/%d %d %d %d\n"), dskdmaen, drv->trackspeed, drv->mfmpos, drv->tracklen, drv->indexoffset, drv->floppybitcounter);
@@ -3414,7 +3423,7 @@ static void updatetrackspeed (drive *drv, int mfmpos)
 {
        if (dskdmaen < DSKDMA_WRITE) {
                int t = drv->tracktiming[mfmpos / 8];
-               int ts = get_floppy_speed2 (drv) * t / 1000;
+               int ts = get_floppy_speed_from_image(drv) * t / 1000;
                if (ts < 700 || ts > 3000) {
                        static int warned;
                        warned++;