|
... until the job is done. Came home from work, only wanted to take another look at my project and ended up routing the circuit board from scratch. Again its the middle of the night, but I now have a first complete version. Electrical checks and layout checks are green, but I will still have to check everything for logical errors before I can have the board manufactured. And there also still is the tiny matter of writing the firmware while waiting for the board to arrive.
Here is a picture[^]
We are the Borg. Resistance is voltage divided by the current.
The language is JavaScript. that of Mordor, which I will not utter here
This is Javascript. If you put big wheels and a racing stripe on a golf cart, it's still a f***ing golf cart.
"I don't know, extraterrestrial?"
"You mean like from space?"
"No, from Canada."
If software development were a circus, we would all be the clowns.
|
|
|
|
|
Thru Hole Forever! 
|
|
|
|
|
The graphics chip, the CDP1861, is out of production since the early 1980s. All the other parts are still in production and available as SMD, so I could save a lot of space. Space is not much of a problem, but manually soldering is. All parts are CMOS (the 74LSXX logic ICs are actually going to be 74HCTXX), so I prefer to have sockets in case I zap one. Also, this way I can first test the board with empty sockets and then add the ICs group by group and measure the signals.
This is my plan:
- Check the entire schematic for logical errors. Twice, better three times.
- Order the board and parts
- Assemble the board, still leaving the sockets empty.
- Check the voltages and look for shorts.
- Add the logic ICs, now we should have a clean clock signal.
- Add the processor and the EPROM with a small test program to blink the LED.
- Add the RAMs and expand the test routine in the EPROM with a memory check.
- Add the graphics chip and expand the test routine to put something on the screen.
- Add the IO port and test the communication with the host computer.
- From here on it's just a matter of developing the software in the EPROM, so that the host can comfortably send graphics commands over the IO port and leave all the dirty work to the processor on this graphics card.
35 years ago I would have commited serious crimes to get my hands on something like this. 
The language is JavaScript. that of Mordor, which I will not utter here
This is Javascript. If you put big wheels and a racing stripe on a golf cart, it's still a f***ing golf cart.
"I don't know, extraterrestrial?"
"You mean like from space?"
"No, from Canada."
If software development were a circus, we would all be the clowns.
|
|
|
|
|
What, you're not laying it out with precision tape and copying it to photoresist yourself? Slacker...
Since the image doesn't render for me, I can't see what you're making, but it sounds like "good old days" to me. Have fun! 
Will Rogers never met me.
|
|
|
|
|
Photoresist? Are you joking? Draw the layout directly onto the copper with an acid proof pen. Those were the days.
The language is JavaScript. that of Mordor, which I will not utter here
This is Javascript. If you put big wheels and a racing stripe on a golf cart, it's still a f***ing golf cart.
"I don't know, extraterrestrial?"
"You mean like from space?"
"No, from Canada."
If software development were a circus, we would all be the clowns.
|
|
|
|
|
We are the Borg. Resistors are futile. You will be integrated.
Bad command or file name. Bad, bad command! Sit! Stay! Staaaay...
|
|
|
|
|
I can only reply with a quote from Darth Vader: No disintegrations!
Edit: Darth seems to agree with the Borg and I wonder if his suit is compatible with Borg tech.
The language is JavaScript. that of Mordor, which I will not utter here
This is Javascript. If you put big wheels and a racing stripe on a golf cart, it's still a f***ing golf cart.
"I don't know, extraterrestrial?"
"You mean like from space?"
"No, from Canada."
If software development were a circus, we would all be the clowns.
|
|
|
|
|
Damn, that's old school....
Looks pretty nice. What was the software used, Eagle?
Ken
|
|
|
|
|
Yes, it's Eagle, courtesy of my boss who does not mind that I take his notebook home and make some stuff for my old computer.
And yes, it is old school. You have to be very lucky or find some chip collector to get the CDP1861 graphics chip. Other parts, like the CDP1802 processor or the CDP1851 IO port are still in poduction and relatively easy to get. The real retro guys would of course be offended because I did not go all the way and got some original parts from 1976 in their white ceramic packages.
The language is JavaScript. that of Mordor, which I will not utter here
This is Javascript. If you put big wheels and a racing stripe on a golf cart, it's still a f***ing golf cart.
"I don't know, extraterrestrial?"
"You mean like from space?"
"No, from Canada."
If software development were a circus, we would all be the clowns.
|
|
|
|
|
I just posted this in Weird & Wonderful[^]
I wrapped the code in PRE tags, yet the code looks unformatted. Anyone else seeing this?
Amy I doing it wrong?
If it's not broken, fix it until it is
|
|
|
|
|
It's Elephanting markdown again - it doesn't like blank lines in code blocks.
Edit the message, remove the blank line. Post the message.
Edit it again, put the blank line back. Post the message.
It'll be fine.
I've reported this a couple of times - it does it with *hello* as well from time to time, and it doesn;t matter if you have markdown enabled or disabled.
POS, markdown...
Bad command or file name. Bad, bad command! Sit! Stay! Staaaay...
|
|
|
|
|
That did it! Thanks
If it's not broken, fix it until it is
|
|
|
|
|
You're welcome!
I get it all the damn time in QA... 
Bad command or file name. Bad, bad command! Sit! Stay! Staaaay...
|
|
|
|
|
Kevin Marois wrote: Amy I doing it wrong?
Who's Amy?
What do you get when you cross a joke with a rhetorical question?
The metaphorical solid rear-end expulsions have impacted the metaphorical motorized bladed rotating air movement mechanism.
Do questions with multiple question marks annoy you???
|
|
|
|
|
Is much better than "Monday The Whatever"
Lol got this as fwd msg. 
Starting to think people post kid pics in their profiles because that was the last time they were cute - Jeremy.
|
|
|
|
|
|
|
Sander Rossel wrote: But why some buildings don't have a 13th floor is beyond me
Really? Surely it's because the roof is over the 12th?
I am not a number. I am a ... no, wait!
|
|
|
|
|
|
We Brits had this all sorted out even before there were buildings that high by calling the 1st floor, the Ground Floor. Thus the 13th floor is numbered 12 and the floor numbered 13 is actually the 14th. The bad luck gets so confused about what floor it's supposed to be on that it simply disappears in a puff of logic.
I am not a number. I am a ... no, wait!
|
|
|
|
|
We Dutch had it all sorted out too, we're just too sober for that kind of superstition crap 
We have a ground floors AND 13th floors
|
|
|
|
|
Yup yup!
I went out to dinner at a casino last night, and hit a Royal Flush on a poker machine while waiting for dinner.
Will Rogers never met me.
|
|
|
|
|
|
Starting to think people post kid pics in their profiles because that was the last time they were cute - Jeremy.
|
|
|
|
|
|
I think the best part would be seeing the look of confusion on many people's faces, while on faces of the chosen few the wry smile of understanding.
“That which can be asserted without evidence, can be dismissed without evidence.”
― Christopher Hitchens
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
