6 Sep
2007
6 Sep
'07
8:11 p.m.
On 9/5/07, Tony Duell <ard at p850ug1.demon.co.uk> wrote:
> Don;'t you mean 7483 here? ...
>
> The 74283 is a 4-bit adder with a more sane pinout (and corner supply pins).
[...]
I did not realize it was a strange-power-pin part. I
would have
figured it out eventually, but it's best to be forwarned.
It's even better to have a TTL databook to hand when working on such
machines. Then you're not tempted to guess.
Actually, that's another advantage of paper databooks. Since the
databooks cover many related chips, you're likely to have the data on
most of the chips in the machine to hand if you have the databooks on
some of them. Whereas if you download infividual datasheets, you'll only
have the data on the chips you've downloaded data for.
Which means that if you're debugging an old machine and come across some
chip you didn't realise was used in said machine, if you have the
databook, you probably have the datahsset, and will look it up. If you
are relying on the web, you might say 'Oh, I know that one' and not
bother to downloasd and print the datasheet. And then spend hours sorting
out a problem due to the fact that you didn't really know said chip...
-tony