5 May
2011
5 May
'11
11:20 p.m.
re:
With the addition of two more Tektronix 4015-1
terminals, I've
rearranged my Tektronix storage tube terminals in the warehouse and
uploaded some updated pictures of "Tektronix storage tube row". (The
4015-1 is essentially a 4014 with APL and printer interface options.)
Neither of the 4015's are reported to be in working condition from the
seller, but at least all the keycaps with APL glyphs are present. The
Wow, lucky!
I used a 4015 for APL programming on a Burroughs B6700 for awhile ...
it took me *decades* to break the habit of clearing the screen when the
cursor got near the bottom :)
I remember when I first saw HP's HP2641 terminal ... I was disappointed it
couldn't do all the overstrikes that the Tektronix 4015 could do.
Of course, the Tek terminal *really did overstrikes*. The HP 2641 read
what was in memory before, considered what was being "overwritten", and
replaced the character in memory with the appropriate combination character ...
if it had one. Otherwise, you'd see only the second character (IIRC).
I.e., it implemented a (small) set of known overstrike characters as separately
encoded characters in ROM, and did a two-character lookup to find one when needed.
OTOH, the 2641 could scroll :)
Stan