Re: [gentoo-user] Re: [WAY OT] wanna learn networking internals

[Alan McKinnon]

On 03/09/2015 21:46, Francisco Ares wrote:
> Me, too, a hardware guy, but having to learn high level stuff. Here at
> the company that work for, we had a programmer a couple of years ago,
> that has gone for a better opportunity. So I got his load.
>
> Blinking a bunch of LEDs is where I started. The first ones with simple
> transistors, resistors and capacitors, TTLs were next, and then,
> finally, a Z80 with an UV EPROM,

Z80? A fine CPU. Built by a bunch of guys who left Intel early on,
convinced a full 8 bit cpu with 16 address lines was possible!

That chip powered so many home pcs in the late 70s and early 80s. That
and the 6502

# having to be programmed at the
> university lab in a terribly monstrous gig

A giant thing with a ZIL socket and huge UV tubes to blank the EPROM>
Yup, I remember them well

> - there was a teletype
> (remember those?)

Golf balls. Gods, those things made a racket.
But worse still was line printers with 136 disks, one for each character
position. If you printed just the right things, you could get them to
play out a tune :-)

> where a paper tape had to be punched with the byte
> codes, hand assembled from mnemonics, the tape transferred to another
> part where it was read while the bytes been burnt to the EPROM; if one
> missed or twisted a byte, everything had to be done again, program tapes
> being literally patched over and over. Nowadays it all look very funny,
> but not at all on those days with a final degree project deadline
> approaching ;-)

Oh no, not punched paper tape. All I remember is thousands of tiny
yellow punched shards that floated everywhere like confetti....

> Thanks for the opportunity for an old story to be remembered.

We old farts here reminisce about every 6 months or so. It usually
starts when someone asks a question like: did you ever work with those
original 8 inch floppies? and the thread goes on for days :-)


-- 
Alan McKinnon
alan.mckinnon@×××××.com