F1: Format cleanups and minor fixes

Refs #73
keirf · Jan 28, 2020 · bccc4d1 · bccc4d1
1 parent 74d9087
commit bccc4d1
Showing 1 changed file with 10 additions and 7 deletions.
diff --git a/libdisk/format/amiga/f1.c b/libdisk/format/amiga/f1.c
@@ -8,7 +8,7 @@
  * RAW TRACK LAYOUT:
  *  u16 4489
  *  u32 0xfe000000 + tracknr
- *  u32 dat[0x5b6] :: even/odd
+ *  u32 dat[0x5b5] :: even/odd
  *  u32 csum
  * Encoding is alternating even/odd, per longword.
  * Checksum is ADD.L over all decoded data longs.
@@ -24,25 +24,25 @@ static void *f1_write_raw(
 
     while (stream_next_bit(s) != -1) {
 
-        uint32_t dat[ti->len/4+1], raw[2], sum, i;
+        uint32_t dat[ti->len/4+2], raw[2], sum, i;
         char *block;
 
         if ((uint16_t)s->word != 0x4489)
             continue;
 
-        ti->data_bitoff = s->index_offset_bc - 31;
+        ti->data_bitoff = s->index_offset_bc - 15;
 
         for (i = sum = 0; i < ARRAY_SIZE(dat); i++) {
             if (stream_next_bytes(s, raw, 8) == -1)
                 goto fail;
             mfm_decode_bytes(bc_mfm_even_odd, 4, raw, &dat[i]);
             sum += be32toh(dat[i]);
         }
-        if (sum != 0)
+        if ((be32toh(dat[0]) != (0xfe000000 | tracknr)) || (sum != 0))
             continue;
 
         block = memalloc(ti->len);
-        memcpy(block, dat, ti->len);
+        memcpy(block, dat+1, ti->len);
         set_all_sectors_valid(ti);
         return block;
     }
@@ -59,7 +59,10 @@ static void f1_read_raw(
 
     tbuf_bits(tbuf, SPEED_AVG, bc_raw, 32, 0x4489);
 
-    for (i = sum = 0; i < ti->len/4; i++) {
+    sum = 0xfe000000 | tracknr;
+    tbuf_bits(tbuf, SPEED_AVG, bc_mfm_even_odd, 32, sum);
+
+    for (i = 0; i < ti->len/4; i++) {
         tbuf_bits(tbuf, SPEED_AVG, bc_mfm_even_odd, 32, be32toh(dat[i]));
         sum += be32toh(dat[i]);
     }
@@ -68,7 +71,7 @@ static void f1_read_raw(
 }
 
 struct track_handler f1_handler = {
-    .bytes_per_sector = 5848,
+    .bytes_per_sector = 5844,
     .nr_sectors = 1,
     .write_raw = f1_write_raw,
     .read_raw = f1_read_raw