[Simh] Question about card readers.

[Paul Koning]

> On May 26, 2016, at 6:05 PM, Clem Cole <clemc at ccc.com> wrote:
> 
> 
> On Thu, May 26, 2016 at 4:56 PM, Mark Pizzolato <Mark at infocomm.com <mailto:Mark at infocomm.com>> wrote:
> I agree.  If this whole discussion is about if a simulated card reader device
> interface should try to magically correct for garbage input (i.e. lines longer
> than card images), then I suggest that the best simulation is to behave as
> closely to how real systems worked. 
> 
> ​The question of what real systems did is open.  IIRC TSS as a system read in all 80 columns, ​but as was pointed out the FTN compiler ignored them.   But not all of them did.   I still have the algol-w compiler source around somewhere in PL/360 -- which might give you a hint

I have never heard of any device that wouldn't give you 80 columns.  Even limited systems like the 1620 which believed that the only I/O encoding was the one it implemented didn't do any such thing.

I just remembered one example of an 80 column card with something beyond column 80, but that isn't really relevant to computer I/O and I don't think computers paid attention. That is the verifying mode of some keypunches (model 129?) where successful verification of the card would cause it to be marked with a punch in "column 81".  

	paul


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