24 Jun
2005
24 Jun
'05
8:32 p.m.
Jim Battle wrote:
Vintage Computer Festival wrote:
I don't know from which Wang system your paper tape came from, but wang was
pretty good about recycling designs to last more than just a point product,
especially back when paper tape was in use and Wang wasn't big enough to afford
redundant engineering.
THe system 2200 hardware pocket guide describes the Model 2203 punched tape
reader like this:
The Model 2203 Punched Tape Reader reads punched tape at a rate of about 300
characters/sec, reading in either forward or reverse direction. It reads
standard one-inch eight-channel tape punched in ASCII code as well as certain
narrower non-standard punched tapes. Reading is done optically.
I have some paper tapes that I'm trying to
read and I have good reason to
believe they are from a Wang machine of some type.
They seem to hold some sort of document. The writing on the tape
indicates a section number and "pages".
The tape is 8-level. The 8th bit seems to be used as some sort of
end-of-line or end-of-record marker. The 7th bit seems to be parity. So
the actual symbol codes are likely 6-bit.
I've read in the tapes and done some cryptanalysis but so far I haven't
been able to see any patterns that would suggest groupings of letters at
certain codes. At this point I'm confused.
Does anyone know how Wang paper tapes were encoded, or does anyone know
where there is technical documentation about this? So for my searches
online have turned up empty.
http://www.thebattles.net/wang/docs/basic-reference.pdf
Page 147 and the next few pages (not of the PDF, but instead page 147 of
the original manual numbering) talks about using the DATALOAD command to
read paper tapes. It has some information that might be useful.