HEPAX File System, file names

[MeindertKuipers]

Thanks for your support, I figured it out. Just a lot of tedious typing and checking to find out. I still need to verify if this works in my disassembler, but here it is (only one file assumed in HEPAX RAM):

Code:


              bit in word  
              9-8   7-6    5-4    3-2    1-0
   [C092]     t24   t25    t26    t27    t28
   [C093]     t14   t15    t16    t17    t18
   [C094]     t4    t5     t6     t7     t8
   [C095]     t19   t20    t21    t22    t23
   [C096]     t9    t10    t11    t12    t13
   [C097]     -     -      t1     t2     t3
   
   If the filename is (assuming a 7-character filename):
   t1.t2.t3.t4 / t5.t6.t7.t8 / t9.t10.t11.t12 / t13.t14.t15.t16 / t17.t18.t19.t20 / t21.t22.t23.t24 / t25.t26.t27.t28

where txx is always a pair of bits (2 bits)

The filename seems to be delimited with a <space> (when shorter than 7 characters), a non assigned file (the first empty in the system) seems to have a name of all spaces.

It is not entirely logical to me, so it would be nice if somehow the background of this choice of coding could ever be available. Now work to verify this en then check if this also applies to the packing of a register in 6 10-bit words.

Strange enough, it is possible to rename a HEPAX file to a name with only one space, or to have a filename with spaces between character, so the delimiting space is not very strict.