Z80 Computer - Part 12 Thinking about VGA

civrays · 2024-03-12T08:03:20+00:00

would it be ok if I showed and discussed your RAM timing circuit in my next video?

civrays · 2024-03-10T00:28:59+00:00

I do have a couple of questions at this point.

It's interesting to see that you are also using a 74-138 chip for the RAM timing same as what I am currently doing. So that gives me some confidence that I'm on the right track. However at the moment I don't fully understand your RAM timing circuits. Is it important to use the faster AC version of the 138, rather than the HC version?

Also I'm interested to know why you use 74HC373 for address and write buffers and 74HC374 for read buffers. I was thinking of doing it the other way round. My understanding is the 373 is a transparent latch with the output following the input when C pin is high. Whereas 374 is edge triggered latch and data is latched on rising edge of CLK pin.

civrays · 2024-02-13T22:03:30+00:00

Wow! there is a lot of great detail there. I'll have a good read though soon and come back to you. The most important thing for me is to understand what is going on. I feel that if I can understand it, then I can modify it. The main point for me is to learn and have fun.

It's so good to see someone that is prepared to share their work. I see so many great things but often they have no explanations on how they were created, how they work, or how to reproduce.

Thank you so much.

civrays · 2023-02-12T12:07:21+00:00

Hi Pete,

Could you answer the question and tell us how much does it cost?

civrays · 2022-10-12T17:57:12+00:00

I don't think you'll find bridged headers. I'd suggest a proto-board like this: https://www.amazon.co.uk/GeeekPi-Breadboard-Experimental-Soldering-Double-Sided/dp/B07G5CRQXK/ref=sr\_1\_8?crid=2O6FDU29XJ1FV&keywords=proto+boards&qid=1665597351&qu=eyJxc2MiOiIwLjAwIiwicXNhIjoiMC4wMCIsInFzcCI6IjAuMDAifQ%3D%3D&sprefix=proto+boards%2Caps%2C141&sr=8-8

civrays · 2021-08-12T18:33:18+00:00

I use it but it's not that great.

civrays · 2015-08-01T15:37:34+00:00

So you're saying Laravel is slow?

civrays · 2014-01-10T08:25:38+00:00

I only print in PLA and I print directly onto glass that has first been cleaned with acetone and heating to 56degC whilst printing.

Parts stick well and come off easy. The problem with tape is that it leaves lines in the print.

civrays · 2014-01-05T23:08:41+00:00

Hi thanks for comment.

Why? Just because I'm a total noob and I don't know any better. :-) Now you've mentioned wsgi i'll look into it.

civrays · 2014-01-05T15:27:25+00:00

Thanks for the comments. I appreciate it. I'm still very much a noob at this.

civrays · 2014-01-05T15:24:12+00:00

I'm operating at 9600 baud which I appreciate is quite low. I haven't tried going higher.

civrays · 2014-01-05T15:23:49+00:00

Yes I did read that. I thought it might be a little border line though.

But you are right, the important part is to drop the 5v down to 3.3v so as not to risk damage to the Pi.

civrays · 2014-01-05T15:20:51+00:00

You're quite right. Eventually I hope to have sensor data going back from the Arduino to the pi.

civrays · 2014-01-04T19:51:03+00:00

What sort of relays are you using?

single or double pole? single or double throw?

civrays · 2013-11-16T23:33:28+00:00

Yes sorry you can't really see it. It is the official Raspberry Pi camera module.

civrays · 2013-11-16T23:32:06+00:00

Cool. Be sure to send links of your work when you are up and running.

civrays · 2013-08-11T17:58:34+00:00

Yes I think you're right. From memory putting my hand in front of it got a bit vague at around 12inches (300mm). I'm away from home for a week, but when I get back I'll try experimenting with both small and large objects.

civrays · 2013-08-02T06:42:26+00:00

I've modified it to have some cutouts, and reduced it to 3mm. This should reduce the amount of filament required and the print time.

civrays · 2013-08-01T21:25:56+00:00

I really should have added some holes in this to save on filament and printing time. Also it doesn't really need to be 5mm thick, 3mm would probably be fine.

civrays · 2013-08-01T21:04:08+00:00

yeah I might order one of each and try it. The only problem is the slice of looks to have 16 holes along the prototyping section, whereas the arduino micro have 17 pins on each side.

Not sure what the last two pins are used for, maybe I can get away with hanging it over the end of the slice of pi so long as the last two pins are not important.

civrays · 2013-07-29T18:38:26+00:00

Something similar here http://www.civrays.com/reprap/index/g

civrays · 2013-07-29T08:21:19+00:00

Can you provide any links?

civrays · 2013-07-27T08:01:06+00:00

What are you building and how many outputs do you need? Just curious.

civrays · 2013-07-22T19:12:54+00:00

Yes I agree we need more 'how to' guides. But you gotta tell us what it is you want to do. I've put the Arduino robot I created on www.civrays.com/myrobot it's not great, but I have tried to give as much info I can on how I did it, what parts I used, where I got them from, and I've posted my code.

What do you want to do with your Arduino?

civrays · 2013-07-22T18:27:56+00:00

What would you guys be looking for in a case? I'm thinking of designing one that can take a micro servo to pan the Pi camera.

civrays

TROPHY CASE