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Altera do some I think, but they were going to BGA last I looked, BGA's are not fun for hand assembly.
It can be done but requires brain surgery levels of coordination. Altera do have CPLDs there are simpler options programming wise (have a look at Texas, Atmel), but I think they have jumped over to BGA's almost exclusively.
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Thanks. I looked for Altera and Atmel and found quite a few devices in PLCC packages. The price was around 2 or 3 bucks each, so that's ok as well. Now I see another problem coming: All of them run at 3.3V or less. I need 5V, but that seems to be completely out of the question.
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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A thing I have done in that situation is use a 5v-3.3v converter locally to power them. I suppose you could use a potential divider as a hill-billy test solution...
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That plus level shifting at the I/O pins kindof defeats the purpose of having less stuff on the boards, right?
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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Yep, but there is always the thing of making the boards too simple, when you get to designing your own computer easy is good, do-not mistake easy and simple for the same thing! 
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Easy is good?
Then I will probably keep the discrete logic. The oldschool method would be to do everything one step at a time and test as much as possible on a breadboard. Once I have the first board running, I can connect it to the breadboard with a ribbon cable and try out each component on the other boards one at a time.
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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Easy is good? -> well in my experience YES, If the circuit has a minimal amount of cleverness then it's easy to find where issues are. Having spent days sorting 'clever' designs to remove one set of chips where the designer though well I can do that in a PLD, don't. Only to find the a bug in the PLD's. I am a fan of getting it to work, then 'simplify' things when you know your base design was working. For instance if you come up with a way of simplifying the connection path try it on one section first get that working, then try the next, it might need some fiddling(R's & C's) to get it right in each case it's used...
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Then how about this:
I could build a bare bones single board computer. The absolute minimum:
- CPU
- a ROM
- a RAM
- address demultiplexer (otherwise it can't address ROM and RAM)
- clock oscillator
- simple bit banged slow RS232 (just two transistors and a few resistors required). If I use a PC power supply, I should also get the required voltages.
- a bus connector
I should have most parts at home and could solder this together. With the bit banged serial port I can load test programs from a PC and run them. Now I can hook up the breadboard to the bus connector and can go one step at a time and test everything before ever having to make any boards.
Edit: I just looked it up: The ATX power supply I use with the breadboards deliver +/- 12V That's well in the specifications of RS232 and will do for the simple bit banged serial port.
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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ATX power supplies, useful but scary amounts of current I have seen them melt the insulation off wires when not treated with care (I have used one for cutting PVC drain pipes!). I know it's a pain but if you go slowly and carefully you can get it done and it will look cool!
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glennPattonWork wrote: I know it's a pain but if you go slowly and carefully you can get it done and it will look cool!
What? The drain pipe?
glennPattonWork wrote: ATX power supplies, useful but scary amounts of current
I have been using it for years now with the circuits on the breadboard. This particular power supply obviously can live well with only a tiny load connected.
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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Quote: glennPattonWork wrote:
I know it's a pain but if you go slowly and carefully you can get it done and it will look cool!Cool |
What? The drain pipe?
Nope the 'puter
I will want to see photos
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There are 20 and 24pin PDip EEPLDs in stock at Mouser.
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Try the Lattice GAL22V10D-25N, still available, DIL Package and works at 5V. I think you need the ISPLever tools for designing.
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To be XOR not to be...
That is the question.
... such stuff as dreams are made on
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True.
modified 13-Sep-18 21:01pm.
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No. x XOR !x always is true.
Besides that, equality is tested with XNOR.
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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CodeWraith wrote: x XOR !x always is true
Under the oversimplifying assumption that be cannot change quickly.
... such stuff as dreams are made on
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megaadam wrote: Under the oversimplifying assumption that be cannot change quickly.
No, still evaluates to true.
"There are three kinds of lies: lies, damned lies and statistics."
- Benjamin Disraeli
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Actually not, if it changes between the two reads. ie:
(true) XOR (not false)
... such stuff as dreams are made on
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megaadam wrote: Actually not, if it changes between the two reads.
In the register? During a single-bit comparison operation? Death NOR taxes move that fast 
"There are three kinds of lies: lies, damned lies and statistics."
- Benjamin Disraeli
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#define be a++
... such stuff as dreams are made on
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Oooh, I love bool bs. 
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That's a bit much (or not).
| Ravings en masse^ |
|---|
| "The difference between genius and stupidity is that genius has its limits." - Albert Einstein | | "If you are searching for perfection in others, then you seek disappointment. If you are seek perfection in yourself, then you will find failure." - Balboos HaGadol Mar 2010 |
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After 5 years, I decided to upgrade the TV in my living room. The question I wanted to ask is if the following features exist on TV.
The Feature is like opposite of Mute. I would like to hear the audio but not the Picture. In other words I want the audio to be heard with the TV monitor screen off/blank!!
cheers,
Super
------------------------------------------
Too much of good is bad,mix some evil in it
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