[Info-vax] AlphaVM-free emulator with all additional peripheral components

[Paul Sture]

On Wed, 01 Aug 2012 23:46:19 -0700, Hans Vlems wrote:

> On 1 aug, 17:01, Paul Sture <p... at sture.ch> wrote:
>> On Wed, 01 Aug 2012 10:30:32 -0400, Stephen Hoffman wrote:
>> > Octets did eventually become the common unit of character encoding,
>> > but that took many years.
>>
>> > The UNIVAC 1100 series running EXEC-8 had 36-bit words, with 6-bit
>> > FIELDATA, and 9-bit ASCII character encodings.  DEC had a few of its
>> > own odd-ball character encodings, and some of the detritus of that
>> > era (eg: RAD50) still lurks in a few very dark corners of VMS.
>>
>> The ICL 1900 series machines used 24 bit words, which could be used as
>> four 6 bit characters.  IIRC parity came into the mix as well, though
>> that might have been on the later 2900 series.
>>
>> ISTR 48 character keyboards from that era.
>>
> 
> IIRC The ICL 1900 used some form of EBCDIC. For sure it wasn't
> compatible with the cards punched on a Burroughs B7700.

According to the Wiki for the 1900 it used "a modification of an early 
version of ASCII, known by ICT as the ECMA character set, with some 
characters in different positions".

But the Wiki for the 2900 used ICL's own form of EBCDIC.

https://en.wikipedia.org/wiki/ICL_1900#Data_formats

https://en.wikipedia.org/wiki/ICL_2900_Series#Addressing_mechanisms

Interestingly the 2900 had the concept of Virtual Machines. Not to be 
confused with what we understand by that phrase today, these were more 
akin to processes or threads on other operating systems.


https://en.wikipedia.org/wiki/ICL_2900_Series#The_Virtual_Machine


-- 
Paul Sture