Changes
/* Disk Paramter Header (DPH) for Drive A/B */
29h 23 ALT Block Allocation Table (23x8bit = 184bit) (only 180bit used)
== Disk Paramter Parameter Header (DPH) for Drive A/B ==
00h 2 XLT Skew Factor Translation (physical-to-logical sector) (not used)
02h 2 TRACK Current Track (misused as DIRNUM by AMSDOS)