Hi,

just found kind of substitution cipher type (i am quite sure it is substitution), but as i see, substitution cipher like ROT13 use the ascii hex in that range too (if the range is A..Z, then it still using that ascii hex range). but what i found is using another hex range (from 00 ...).

i.e. input :
ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz

output:
1B 18 19 1E 1F 1C 1D 12 13 10 11 16 17 14 15 0A 0B 08 09 0E 0F 0C 0D 02 03 00 7A 3B 38 39 3E 3F 3C 3D 32 33 30 31 36 37 34 35 2A 2B 28 29 2E 2F 2C 2D 22 23 20

i knew its kind of being read back and forth every 2 sequence, kind of big end<>little end thing. anyone know what cipher is this?