1 Aug
2026
1 Aug
'26
11:42 p.m.
Rich Alderson via cctalk <cctalk(a)classiccmp.org> writes:
Just out of curiosity, what is the internal format of
these images?
Most especially, what is the internal format of the "18 bit" file?
All PDP-6/10 DECtape images I have seen (and I assume this also applies
to any 18-bit image) have each block being 256 32-bit little endian
words. Each word stores an 18-bit number. For a 36-bit tape, the words
are paired to form 128 36-bit numbers. The number of blocks are
typically around 576. There is no low-level format info.