Real Old School Programming (was: Re: Where to buy a Selectric?)

[Chuck Guzis]

On 1/1/2006 at 3:12 PM Mike Loewen wrote:

>    It's the real deal, as far as I know.  I know next to nothing about
>CDC 
>systems.  The sign says it's a model 6600, serial number 1.

I recall a CE friend once telling me that he'd worked on that particular
system and that the divide unit had been modified considerably such that it
didn't deliver the same results as any of the other 6600's.   It might be
that SN 1 is so old that it wasn't possible to put CEJ into it without
rebuilding the whole darned thing.

The DS program in the CDC reference manual makes no sense from an IPL
standpoint on a stock 6600:

0001	7505		DCN		5
0002	7705 2020	FNC		2020,5  
0004	1437		LDN		37
0005	7405		ACN		5
0006	7305 0011	OAM		11,5
0010	0300		UJN		0		(hang)
0011	4005
0012	0011
0013	0000
0014	0000

Since, at deadstart, PP5 would be active and waiting for input on channel
5, the code makes no sense.  My best guess is that the photographer shot a
photo of a lashup with 4 PPs or less used for debugging the I/O interface
at Chippewa Falls.

Cheers,
Chuck