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No, not me. My favorite little microprocessor. It was introduced in 1976 by RCA. Only a few years after the microprocessor was officially invented, it offered some features which made it very innovative at the time. Too innovative for some people who called it 'strange' or an 'odd beast'.
Like its predecessor, the (two chip) CDP1801, it was built in CMOS technology. RCA built the computers for space probes and became a pioneer in CMOS (they called it COSMOS  ) technology because CMOS offers higher noise immunity and extremely low power consumption when compared to other technologies. It also was considered o be slow, because those advantages are based on pairs of MOSFETS (CMOS transistors) doing the switching in the gates. Also, needing twice as many transistors for a gate was not helpful with the very limited densities on a chip.
Today practically everything is CMOS. Processors use billions of MOSFETS and at their high clock frequency they get very hot, despite the low power consumption of CMOS. They would instantly burst into flames if you could magically change the technology.
Besides driving a (relatively) typical microprocessor bus, the CDP1802 offered a few general purpose IO lines which could be controlled by machine language instructions, like microcontrollers. Later versions even had onboard ROM and RAM, resembling a modern microcontroller even more. This hybrid design may appear strange, but it allowed to build very compact single board computers with only very few ICs besides the CPU itself. In my old computer a single output bit did triple duty as rudimentary sound generator, the output signal to the cassete recorder to save programs and the output line of the RS232 serial port. Sound generation, loading and saving from tape and serial communication were done by the CPU in software, only one at a time of course.
And now the 'oddest' feature. The processor does not have many addressing modes. Everything is done by loading an address into a register and access memory over this pointer. Addressing modes are emulated by manipulating the address in the register. Period. That's it. The processor does not even have a stack pointer or a program counter, just generous 16 general purpose registers. You just load an address into any register and designate it to be the program counter or stack pointer. Back then people had no other word than 'strange' for this. It appeared to be spartan, almost primitive. While there was lots of room for improvement, it also easy to understand. I probably could get most people here to write machine code for this little processor within an hour. Later, a similar concept became very sucessful. The most widely used processor of all times uses it and even Intel CPUs use it to implement their complex instruction set in microcode. It's not called 'strange' anymore. Today it's called RISC.
For a few months I have now been designing a 'reboot' of my old computer. It shares much of the old design, but drops the anachronisms. How about a real serial port instead of letting the CPU tag along with 300 baud? How about up 16 megabytes ROM and RAM. Or perhaps delegating IO and graphics to separate CPUs and letting the main CPU run full blast without having to care about interrupts or DMA?
Of all things, the keyboard is still a problem. Kyboards with their own encoder that hook up to the parallel port can only be found in museums. Instead, I could
- Butcher a cherry keyboard for he key switches, pay a chip collector a generous ransom for the (hopefully functional) encoder (a CDP1871), make a costly circuit board and build a brand new oldschool keyboard. This will be somewhat expensive, but easily last another 40 years.
- Program a microcontroller or use a handful of cheap discrete CMOS ICs to build a PS/2 port. I have some PS/2 keyboards lying around and as bonus I can also add a mouse port. This option is not too expensive, but a little too modern for those who like everything to be 'original'. On the other hand: I have a complete and functional old computer which will be left as it is.
- Something really unusual, like tearing the microcontroller out of a PC keyboard, hooking up the key matrix to the CPU bus and an input port. Then the CPU can make dummy memory accesses to scan the keyboard's columns and monitor the input port for responses on the keyboard's rows. This costs next to nothing if you have a keyboard to butcher, but the keyboard will be connected over a wide and awkwardly short ribbon cable. Besides that, the CPU will have to scan and decode the keyboard constantly.
This really is fun. After all those years I finally get my old computer as I always wanted it. Simply buying a Raspberry Pi or something like that would be boring.
Would this little project be of any interest as an article or shall I leave you alone with this dusty oldschool stuff?
Edit: Oooops. This got longer than i thought.
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.
modified 14-Jul-16 4:54am.
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Write an article about about this nerdgasm?
By all means do, please, pretty please, pretty please with a cheery on top! 
"I had the right to remain silent, but I didn't have the ability!"
Ron White, Comedian
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Manfred Rudolf Bihy wrote: Write an article about about this nerdgasm?
Definitely. When I started soldering in 1978, the short era of homebuit computers already was coming to its end. It was a great time for Nrds. There were no rules and everybody built or programmed something as he thought it was right. And then you presented your results to other nerds who immediatly started improving it or discussing it to death. The first software I bought was a debugger and I remember calling the man who wrote it all across the US to talk about some changes. My parents grounded me and took away the computer when they got he telephone bill.
I used the spare time in my room to build a small Z-80 computer from my parts box
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.
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Article, definitely! 
Bad command or file name. Bad, bad command! Sit! Stay! Staaaay...
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Reminds me of the ZX81 I put together along with hard wiring an old surplus IBM keyboard to use with it.
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So we are looking at the revers engineering of a major users engine that is so unwieldy it can no longer be supported. It take a minimum of 3 months to change and test a rule!
As it is a very large core requirement it will be done by the IT team. They are proposing Java over a Hadoop data store using Drools as the rules engine. As my experience in this area is extremely limited I put it to the hive mind.
Is Drools a viable rules engine for a very large and complex set of rules. I fear it is like Biz talk is to ETL, designed for "power users" to maintain!
Never underestimate the power of human stupidity
RAH
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That sounds like CVDD (Curriculum Vitae driven design) going on right there...
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Thankfully I won't be coding this one, just trying to ride herd on them from a design POV.
Never underestimate the power of human stupidity
RAH
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I'd suggest you do a "five whys" analysis 
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Yeah - you'd think they picked this so they can hire a very specific person. In my chemist days, there would be employment offerings that were extraordinarily specific in nature. To find a citizen with these mandatory traits would command a princely sum and they'd offer chump-change. Along comes the H1b visa*.
* now they had an employee who they could underpay and who couldn't legally change employers or quit.
| Ravings en masse^ |
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| "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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Define what the rules should be and see what that engine can do ? 
I mean you do have requirements and it should not be too hard to get the technical details of the things that should fulfill these, right? Ask a demo, have them prepare a technical document with the solutions.
You're right to ask questions and to be sceptic about something that is complex. Perhaps it's a good tool, perhaps not, it's up to them to prove it
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The helpline for people who have difficulty coping with improper fractions is open 24/7.
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Yes, but the dividends are GREAT!
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May I quotient you on that?
| Ravings en masse^ |
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| "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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Movie Quote Of The Day
When the world slips you a Jeffrey, stroke the furry wall.
Which movie?
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Jeffrey Bourne vs James Bond
In Word you can only store 2 bytes. That is why I use Writer.
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Games of Archons, Despots and Kings.
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Jeffrey Does Dallas! 
Anything that is unrelated to elephants is irrelephant
Anonymous
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The problem with quotes on the internet is that you can never tell if they're genuine
Winston Churchill, 1944
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I'd just like a chance to prove that money can't make me happy.
Me, all the time
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Up In Smoke
Mongo: Mongo only pawn... in game of life.
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My little Pony?
Rules for the FOSW ![ ^]
if(this.signature != "")
{
MessageBox.Show("This is my signature: " + Environment.NewLine + signature);
}
else
{
MessageBox.Show("404-Signature not found");
}
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That's got to be Rainbow[^] the movie. 
"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer
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Over here in Japan traffic lights are horizontal with red on the right. In areas with heavy snowfall they are vertical with red at the top.
Back in my country, they were also vertical.
I think some countries have horizontal ones with green on the right, like the US and Thailand IIRC. I hope there are no places with red at the bottom.
If there are international drivers licenses, surely there should be an international standard for traffic lights too? Things can get confusing if you travel frequently and are colorblind. Of course since we can't agree on which side of the road to drive on, it is not really surprising.
The ones in the US that hang overhead are good because it is hard to miss seeing them. I don't see what advantages horizontal ones have, maybe cost? (Cheaper to mount because they can be lower?)
The colored arrows are particularly treacherous. Here there are green arrows to indicate which directions you can go. Australia also had red arrows too to indicate which directions should stop. And yellow arrows for trams (or are there? I don't remember that well)
Personally I prefer roundabouts. There aren't any here, just millions of unsynchronized lights without sensors that make you stop every 100m even when there is no traffic on the cross roads. Maybe they want to teach us patience.
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Indivara wrote: Australia also had red arrows too to indicate which directions should stop. And yellow arrows for trams (or are there? I don't remember that well)
No yellow arrows for trams, but those tram specific ones are illuminated in T shape. Traffic signals and rules involving trams here could be somewhat complicated:
Hook turns: If you want to turn right, be on the left lane[^] because trams are worshiped here. You'd occasionally observe one noob sitting confused in the hook stop and a bunch of angry drivers literally forcing his car to move ahead with the pressure waves generated by their incessant honking. And some would actually drive past him on his right side (illegally), leaving him in the hook stop so that the traffic on the west->east lane to start honking when they get their green signal.
Tram traffic indicators:
I've seen them to be illuminated red[^], amber[^], AND white[^], and I think that white mean that trams can go (not sure why isn't it green). And the there are signals indicating that trams don't have to worry about the traffic signals displayed, like in this mother of all traffic lights[^].
modified 13-Jul-16 22:47pm.
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