The Flexowriter used as input and output device does not have a key for the digit 1; as with many early cheap typewriters, the small letter l is used. Unfortunately, many tapes, translated to ASCII, do not map to the digit 1.
Designed for scientific and technical cacluations, the data word is a 31-bit fixed point fractional number, i.e. representing numbers from -1 .. +1, both excluded. There is a 32th bit at the least significant position, which is always zero, so all externally shown numbers in 8-digit hex representation are even. For scaling to other ranges, see the manuals.