LED displays (TIL305, TIL308, etc.)

[Roy J. Tellason]

On Wednesday 01 October 2008 16:26, Tony Duell wrote:
> > On Tuesday 30 September 2008 16:43, Chuck Guzis wrote:
> > > Didn't Motorola package one if its early mask-programmed RTL ROMs as
> > > a standard BCD-to-seven segment part?
> >
> > I remember that,  but if you wanted more bits either way than the number
> > of bits the chip was set up for their app info had you cascading some
> > absurd number of them.
>
> I can't think of why you'd want to cascaed 7-segment decoders in this
> way, and wonder if you're thinking of the BCD <-> binary converter chips
> that wrre in the Texas TTL range (and which were, I think, programmed
> ROMs). 74184 and 74185 I think.

Whoops,  you're right,  that's exactly what I was thinking of,  though I'm 
pretty sure I was also remembering Motorola...

Perhaps one of those two companies was second-sourcing the other.

All of my databooks are currently in boxes,  and I'm not even sure which ones 
are in what boxes,  a situation that I'm hoping to correct somtime soon,  so 
I can't verify my recollection on this.

> Cascading thos certainly used a lot of said chips, and it was not obvious
> at first glance how to extend the cascading for an arbitrary word size.

Yes.

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