When you enter DFL-WDII hdd repair program, you can find from above interface SPT field and one button called ‘Get SPT’.
SPT=sectors per track
When the HDD is not detected, the SPT is not read at all and the SPT text box can be empty.
‘Get SPT’ is to execute one special WD hdd factory command to get the SPT value (Please note: this way of getting SPT is not getting it from the FW modules.) Let’s take 1590 series as example. Even if the SA is formatted and you can acquire the SPT value by clicking ‘Get SPT’.
Besides, if you load overlay/module 11, the program will detect and output automatically a correct SPT value too. This is unique and I didn't find in other hdd repair tools.
A correct SPT value is important when you’re going to operate track related functions.