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Re: DMX Output board for 6502 based systems
Posted: Sun May 05, 2024 12:18 pm
by Dr Jefyll
I also mix 74LS with 74HC
OK, fair enough... it
is often possible to get away with that. (And the same is sometimes true for omitting bypass caps).
Just be aware that, when these practices
do cause trouble, the symptoms can be
very inconsistent and misleading. A situation like that can really drive you crazy... you can end up with hours and hours of pure frustration, rather than enjoying the hobby as you would hope to do.
So, there's an element of risk taking. I hope you never have a bad experience. But if you do, it might really change your outlook.
What spurred your interest in DMX, BTW?
-- Jeff
Re: DMX Output board for 6502 based systems
Posted: Sun May 05, 2024 1:41 pm
by barnacle
He suddenly saw the light!
(okay, sorry, yes, that's my coat, thanks!
)
Neil
Re: DMX Output board for 6502 based systems
Posted: Sun May 05, 2024 3:49 pm
by Dr Jefyll
A
spot of humor, eh, Neil?
How 'bout this... !
- a lighting designer knows well
how to color a flood with a gel.
But Neil startled Jan Lemming,
She said, next time use a fresnel!
-- Jeff
Re: DMX Output board for 6502 based systems
Posted: Sun May 05, 2024 7:41 pm
by barnacle
But at the risk of stretching your rhyme even further: she was (is!)
Jan Leeming...
Neil
Re: DMX Output board for 6502 based systems
Posted: Sun May 05, 2024 8:32 pm
by BigDumbDinosaur
- a lighting designer knows well
how to color a flood with a gel.
But Neil startled Jan Lemming,
She said, next time use a fresnel!
<GROAN> 
Re: DMX Output board for 6502 based systems
Posted: Sun May 05, 2024 8:52 pm
by BigDumbDinosaur
okay, forgot to mention I'm using - not only but as many i can - used parts, wich I took off from 80's Olivetti computer pcb...I know that for the purists it's awful but I also mix 74LS with 74HC, as long as they work togheter for me is fine...
Ditto what Jeff said.
It’s not a matter of “purists” thinking the mixing of logic families (CMOS vs. TTL) is “awful.” I don’t think any of us are ”purists” when we design and build using accepted practices. Also, I have no stake in what you are doing, nor will I gnash my teeth when your device fails to operate, or is intermittent, due to mismatched logic. Just be aware that you are, sooner or later, going to run into a difficult-to-diagnose problem with your somewhat-cavalier design approach.
Autodidactic learning is fine, but should tempered with a willingness to accept good advice when it comes your way. When it comes to digital electronics, you would do well to take Jeff’s gentle suggestions to heart.