Incorrect number of formatted HDD sectors (XTA interface)

[barotto]

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whenever i format/install the type 35 HDD on IBMulator, somehow the disk get's a bit bigger than the physical ones (should have 15,125 allocation units/clusters but it has 15,133 instead. Same with the number of sectors... should have 60.654 but it has 60.687 instead. It also reports 33 relative sectors and the physical disk reports 66...). I'm sending you a copy of the type 35 HDD i made using 86Box and a few screenshots and maybe you can figure out what is happening. I used Norton's SYSINFO to get the info.

For the type 40 HDD, it must be installed/formatted with the 1.4 version of the DOS PS/1 INSTALL.EXE (it formats 96% of the whole disk, while 1.0 version formats it to 100%, giving more space but bad clusters appear at the end, even though the disk is ok - same thing happens on 86Box).

Type 35 should be:
physical hdd: 30.976.000
60.500 sectors x 512 = 30.976.000
bytes per sector: 512
(15.125 clusters) (sectors per cluster: 4)

ibmulator: 30.992.384
60.532 sectors x 512 = 30.992.384
bytes per sector: 512
(15.133 clusters) (sectors per cluster: 4)

Type 40 should be formatted with the v1.4 install program to:
physical hdd: 40.617.984
(19.833 clusters)

type35.img.zip