Questions tagged [dec]
For questions regarding the hardware, software and peripheral products of DEC - The Digital Equipment Corporation.
46
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DEC's "decimal ASCII"?
I'm reading some older FOCAL documents and see references to things like...
SETS X TO THE DECIMAL ASCII CODE OF THE INPUT CHARACTER
A bit later there is a table of these codes, and unless I am not ...
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3
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0
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Original DECUS version of Sumer in FOCAL?
I was sure I had a copy of Diamont's Sumer in FOCAL, but now I can't find a trace of it on my machines or online.
Does anyone have a copy of the original code?
- 20.5k
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What was this mini-computer tape troubleshooting process
Back in the early 1980s I worked at a bank. My department input data into a mini-computer which was then to a mainframe system each day. I'm pretty sure it was a DEC mini, if only because the ...
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What disk packs are compatible with the DEC RM05?
While the majority of DEC's PDP-11 systems used UNIBUS or QBUS based peripherals for storage, some of the larger PDP-11s, along with larger machines such as the DECsystem 20 and the VAX-11/780 used ...
- 31
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What did Richard Stallman have against VMS?
Richard Stallman of course was an advocate of free software, and VMS was proprietary, so he would've disapproved of it on that basis alone. (To be clear, I am not discussing here whether he was right ...
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2
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0
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DEC RdbStar information?
I'm putting together an article on TPC-C, and while chasing down leads its primary author mentioned the RdbStar project at DEC.
As he described it, the manager of DEC's storage department (Jim Grey? ...
- 20.5k
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3
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Performance characteristics of the DEC Type 30 graphical display
The DEC Type 30 was an early vector graphics display, that was used for an astonishingly wide range of applications for the 1960s. It used a 16-inch circular CRT with high persistence phosphor ...
- 63.1k
5
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Understanding PALcode
Reading over some old articles on Alpha I realized I really didn't understand PALcode. So I did a little reading on that.
PALcode is stored in main memory, is written in Alpha ML, and is called by a ...
- 20.5k
14
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Did the PDP-8 designers consider a stack?
The PDP-8 was a remarkable exercise in minimalist computer design; some of the aspects of its design are discussed in detail at PDP-8 transistor count
One feature it did not have was a stack. Instead, ...
- 63.1k
5
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3
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Was there an analog of local labels in the IBM assembly language?
In the assembly language used in Unix on DEC machines (PDP-11, VAX), one can use numerical labels and refer to them with suffixes "b" and "f" meaning "backwards" and &...
- 19.4k
6
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2
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Behavior of DECDHL on single lines
The escape sequences ESC # 3 and ESC # 4 (DECDHL) are meant to be used on pairs on adjacent lines to request double height lines. As an example:
echo -e "\e#3DOUBLE HEIGHT LINE\n\e#4DOUBLE HEIGHT ...
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Porting of software from the m68k family architecture to the DEC VAX
I am looking for impressions, memoirs, articles, guidelines - everything that is possible about the unusual direction of software migration. I am interested in non-Unix related code, and preferably ...
- 2,191
8
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2
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Why was the VT05 resolution 72×20?
According to https://en.wikipedia.org/wiki/VT05
the VT05 presented the user with an upper-case only ASCII character display of 20 rows by 72 columns.
At first glance this seems a reasonably natural ...
- 63.1k
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Advantage of RS-232 over 20mA current loop
According to https://en.wikipedia.org/wiki/VT52
Like other early DEC terminals, the VT50 series were equipped with both an RS-232 port as well as a 20mA current loop, an older serial standard used ...
- 63.1k
6
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What was a DEC PDP-11/85 intended to be, and why might it be able to use DECsystem-10 software?
In this DEC PDP-11 Strategy Memo from Sept 1974, there is this curious question.
HOW MUCH OF THE DEC SYSTEM 10 SOFTWARE
CAN THE 11/85 USE, OR DOES THE 11/85 HAVE
TO START FROM SCRATCH?
CONFLICTING ...
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