New Light on the Legend of Mel

[Joseph Monzo]

It is a common misapprehension that octal is in some sense more
"archaic" than hex (I've been a victim of it myself). Granted, modern
computers almost invariably use hex, but even some quite old ones did.

I remember reading that Turing (yes that Turing) used base-32 arithmetic
to describe coding for some machine that used 5-level paper tape for I/O.
The Bendix G-15 (29 bits per word, as is now known to all spectators
at Usenix Jeopardy) used UVWXYZ for the hexadecimal digits above 9.
There's nothing quite so final as ZZZZZZZ, in my observation.
When the computer was annoyed with the operator, its generic error message
was Z0ZZ Y00.
carl
--
carl lowenstein marine physical lab u.c. san diego

In fact according to its Programming Manual of 1957, the LGP-30 did use
hexadecimal, but using F G J K Q W for 10 11 12 13 14 15.

Joseph Monzo
http://tonalsoft.com

[Charles Richmond]

Post by Joseph Monzo

It is a common misapprehension that octal is in some sense more
"archaic" than hex (I've been a victim of it myself). Granted, modern
computers almost invariably use hex, but even some quite old ones did.

I remember reading that Turing (yes that Turing) used base-32 arithmetic
to describe coding for some machine that used 5-level paper tape for I/O.
The Bendix G-15 (29 bits per word, as is now known to all spectators
at Usenix Jeopardy) used UVWXYZ for the hexadecimal digits above 9.
There's nothing quite so final as ZZZZZZZ, in my observation.
When the computer was annoyed with the operator, its generic error message
was Z0ZZ Y00.
carl
--
carl lowenstein marine physical lab u.c. san diego

In fact according to its Programming Manual of 1957, the LGP-30 did use
hexadecimal, but using F G J K Q W for 10 11 12 13 14 15.
Joseph Monzo
http://tonalsoft.com

I have heard of using K S N J F L for 10 11 12 13 14 15 on the Illiac
II, but I did *not* know about the F G J K Q W on the LGP-30.

Interesting...

[Quadibloc]

Post by Charles Richmond
I have heard of using K S N J F L for 10 11 12 13 14 15 on the Illiac
II, but I did *not* know about the F G J K Q W on the LGP-30.

A web page on my site lists all the alternatives I know of:

10 11 12 13 14 15
System/360 A B C D E F
C a b c d e f
Bendix G-15, SWAC u v w x y z
Monrobot XI S T U V W X
Datamatic D-1000 b c d e f g
Elbit 100 B C D E F G
LGP-30 f g j k q w
ILLIAC k s n j f l
Pacific Data Systems 1020 L C A S M D

John Savard

[Dennis Boone]

Do you happen to know the menemonics commonly used for the LGP or PDS
systems? I think the IAS machine (MISTIC, ILLIAC, etc) one is widely
reported.

De

[Quadibloc]

Post by Dennis Boone
Do you happen to know the menemonics commonly used for the LGP or PDS
systems? I think the IAS machine (MISTIC, ILLIAC, etc) one is widely
reported.

No, in general I got the information from manuals on Bitsavers.

In addition to the usual one for the ILLIAC, "King Size Numbers Just for Laughs", a
search turned up an alternate: "Kind souls never josh fat ladies".

A similar search for the Pacific Data Systems sequence turned up no results.

But I *did* find some for the LGP-30.

FiberGlass Javelins Kill Quite Well
For God and Jesus Khrist(os), Quit Worrying

John Savard

[Quadibloc]

Post by Dennis Boone
Do you happen to know the menemonics commonly used for the LGP or PDS
systems? I think the IAS machine (MISTIC, ILLIAC, etc) one is widely
reported.

While Google did not help me find what mnemonic was actually used for
the PDS system, it does occur to me that its sequence of letters actually
lends itself to a mnemonic; something like

Lovely Computer Arithmetic; Some More Digits

John Savard

[Phil Howell]

For those with more than a passing interest in this , here are a couple of links
Lgp30
http://obsolescenceguaranteed.blogspot.com/2016/06/using-simh-lgp-30-emulator.html?m=1

http://www.e-basteln.de/computing/lgp30/lgp30/

[Quadibloc]

2 Surely they didn't use hexadecimal?

Oh yes they did.

However, this was before the IBM 360, and before C, so they chose their own way
to represent the digits beyond 9:

0123456789fgjkqw

John Savard

[Christian Corti]

Post by Joseph Monzo
In fact according to its Programming Manual of 1957, the LGP-30 did use
hexadecimal, but using F G J K Q W for 10 11 12 13 14 15.

Obviously... they directly used the 4-bit representation of the
Flexowriter code.
In fact, you can use other characters for 10..15 as long as the lower
four bits have the value 10..15, so instead of FGJKQW you can write
UTHCAS.
You can even replace 0..9 with ZBYRIDNMPE (or the other way round).

All this of coure only with 4-bit input ;-)

Christian