fixed a bug in mkfat

chPhysDriveNumber is set to 0x80 only for non-floppy media types (or floppy boot code could fail)

FATtools/FAT.py

@@ -41,7 +41,7 @@ class boot_fat32(object):
     0x30: ('wFSISector', '<H'), # usually 1
     0x32: ('wBootCopySector', '<H'), # 0x0000 or 0xFFFF if unused, usually 6
     0x34: ('chReserved', '12s'),
-    0x40: ('chPhysDriveNumber', 'B'),
+    0x40: ('chPhysDriveNumber', 'B'), # 00h=floppy, 80h=fixed (used by boot code)
     0x41: ('chFlags', 'B'),
     0x42: ('chExtBootSignature', 'B'), # 0x28 or 0x29 (zero if following id, label and FS type absent)
     0x43: ('dwVolumeID', '<I'),
@@ -158,7 +158,7 @@ class boot_fat16(object):
     0x1A: ('wHeads', '<H'),
     0x1C: ('dwHiddenSectors', '<I'),
     0x20: ('dwTotalSectors', '<I'),
-    0x24: ('chPhysDriveNumber', 'B'),
+    0x24: ('chPhysDriveNumber', 'B'), # 00h=floppy, 80h=fixed (used by boot code)
     0x25: ('uchCurrentHead', 'B'), # unused
     0x26: ('uchSignature', 'B'), # 0x28 or 0x29 (zero if following id, label and FS type absent)
     0x27: ('dwVolumeID', '<I'),

FATtools/mkfat.py

@@ -260,7 +260,8 @@ def fat_mkfs(stream, size, sector=512, params={}):
         boot.wSectorsPerFAT = fsinfo['fat_size']//sector
     else:
         boot.dwSectorsPerFAT = fsinfo['fat_size']//sector
-    boot.chPhysDriveNumber = 0x80
+    if media_byte != 0xF0: # if not floppy
+        boot.chPhysDriveNumber = 0x80
     if fat_bits != 32:
         boot.uchSignature = 0x29
     else:

FATtools/version.py

@@ -1 +1 @@
-__version__ = '1.0.33'
+__version__ = '1.0.34'