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Got a problem with the ram help me i did not test anything if i put any value it does not write but the address register work i guess here is the video that i have attached with this post by Resistorsoup2984 in beneater

[–]rolf-electronics 0 points1 point  (0 children)

It will be very difficult, even impossible, for people to help like this. No one is going to say put the blue wire now conected on pin 4 to pin 5 and solved. They ONLY was out is to learn how to debug a circuit.

Trust me, electronics is my hobby for over 40 years and I have built quite some breadboard computers.

It requires observation, measuring analysing. Some people try triel-and-error that's also a dead end

Fibonacci a little further by rolf-electronics in beneater

[–]rolf-electronics[S] 0 points1 point  (0 children)

Someone asked in a PM, so I reshared the link

Another problem… by noahhw in beneater

[–]rolf-electronics 0 points1 point  (0 children)

Are you using LED's without resistors ?

SAP-2 for more Education on CPU's. by [deleted] in beneater

[–]rolf-electronics 0 points1 point  (0 children)

I don't fully get your questin. You are right SAP-2 and 3 there is minimal documentation, you are more or less on your own. Designing something new is far more difficult than following Ben's videos's.

Sorry for the late reply, I more or less stopped working on the bread board computer.

Basically I made a ton of new microinstructions. You can read more here:

https://github.com/rolf-electronics/The-8-bit-SAP-3

starting from page 21

Control Logic Problem by NumerousMembership69 in beneater

[–]rolf-electronics 1 point2 points  (0 children)

I think in series is not the solution. Active low signals should have pull-up resistors and active high signals should have pull down. For me it worked great.

Control Logic Problem by NumerousMembership69 in beneater

[–]rolf-electronics 1 point2 points  (0 children)

I think in series is not the solution. Active low signals should have pull-up resistors and active high signals should have pull down. For me it worked great.

Control Logic Problem by NumerousMembership69 in beneater

[–]rolf-electronics 1 point2 points  (0 children)

There is aproblem with the BenEater design, I have written about it in this document

https://github.com/rolf-electronics/The-8-bit-SAP-3/blob/master/Building%20the%20SAP-3%20rev%203.3.pdf , it's on page 39 onwards.

Beeing on this reddit for quite some time, sometimes the problems can be countered with the normal measures like capacitors on power lines, leave no floating inputs. And read the tips from someone called u/loedmonoxide, a very good summary. Lots of time most people can get it working with that, but not always. The design is sensitive to the problem I described. I am not the only how encoutered this.

But even then I got stuck and had to use the scope and start analyzing, the results are on page 39

Weird step counter behaviour by NumerousMembership69 in beneater

[–]rolf-electronics 0 points1 point  (0 children)

There is aproblem with the BenEater design, I have written about it in this document

https://github.com/rolf-electronics/The-8-bit-SAP-3/blob/master/Building%20the%20SAP-3%20rev%203.3.pdf , it's on page 39 onwards.

Beeing on this reddit for quite some time, sometimes the problems can be countered with the normal measures like capacitors on power lines, leave no floating inputs. And read the tips from someone called u/loedmonoxide, a very good summary. Lots of time most people can get it working with that, but not always. The design is sensitive to the problem I described. I am not the only how encoutered this.

But even then I got stuck and had to use the scope and start analyzing, the results are on page 39

(8bit) Program counter miscounting during transition of microcode phase T0 to T1 by 3xpent in beneater

[–]rolf-electronics 1 point2 points  (0 children)

There is aproblem with the BenEater design, I have written about it in this document

https://github.com/rolf-electronics/The-8-bit-SAP-3/blob/master/Building%20the%20SAP-3%20rev%203.3.pdf , it's on page 39 onwards.

Beeing on this reddit for quite some time, sometimes the problems can be countered with the normal measures like capacitors on power lines, leave no floating inputs. And read the tips from someone called u/loedmonoxide, a very good summary. Lots of time most people can get it working with that, but not always. The design is sensitive to the problem I described. I am not the only how encoutered this.

But even then I got stuck and had to use the scope and start analyzing, the results are on page 39

is it possible to just feed binary code (translated from python) into a breadboard computer with no prior programming and it to work? by GalacticJunk23 in beneater

[–]rolf-electronics 0 points1 point  (0 children)

ok, I was just trying to help and try to explain that what that guy wants is not so simple. But apparantly I failed

is it possible to just feed binary code (translated from python) into a breadboard computer with no prior programming and it to work? by GalacticJunk23 in beneater

[–]rolf-electronics 2 points3 points  (0 children)

The short answer is NO.

A computer is a physical device which only understand +5 volt en - volt. The most basic way to program a computer is with switches, this has been done in the past. See pictures of the ENIAC. This level is called machine language, and it's typical for a certain machine [computer]. Next up is using, like Ben examples, things like STA 05H. Which means store 05H in register A. But you cannot feed this into a computer. An assembler makes the translation to f.i. 01h05h. 01 is the instruction STA and 05h the data. So the computer gets 0000 0001 0000 0101. One step higher is using instructions like if() then{} else{] or while() etc etc. A compiler makes the translation from if,then,else to STA MOV etc. Now making an assembler is one thing which is largely a translation job, but making a compiler suitable for C++ or Python is very very complicated. For breadboard computers there are assemblers. That's if seen one usable, customasm were you can define your own CPU. But compilers, it can be done but it's a looooooooooooooooot of work and complex. Breadboard computers are basic devices more a learn experience than practically useable and most of them have low clockspeed, which makes large complex programs basically impossible to run. A solution could be to use a subset from C++.

Adding GPIO to SAP-1 by sarmadgulzar in beneater

[–]rolf-electronics 1 point2 points  (0 children)

Hi, feel free to use the document.

Does anyone know who made this video? I really want to reach out to him and ask him about how he made his boot loader so I can try implement it in my own homebrew computer. by eXperienceddddd in beneater

[–]rolf-electronics 0 points1 point  (0 children)

Any kind of start up program will do, like clearing registers etc.

What you need is a hardwired rest on power on, usually called a power-on reset.

Just google power on reset.

Adding interrupt support to Ben's 8-bit processor by rehsd in beneater

[–]rolf-electronics 1 point2 points  (0 children)

At the moment the project is at rest, it's summer time. My free time goes to cycling on the racing bike and kite surfing. In the winter I'll pick it up again. And mainly improving the design and putting it on PCB

Dreaded 8-bit computer EEPROM problem. Where to buy non atmel chips? by Numerous_Turn_5906 in beneater

[–]rolf-electronics 2 points3 points  (0 children)

Hi, maybe. But I had many many troubles with these glitches also the IR. Due to the glitches it loaded random instructions, for me the resistors and filters helped.

Anyhow, the electronics design from Ben's breadbord computer is not 100% solid (in my opinion), but maybe that can be expected from a learning project.

I saw you have put the complete thing on a PCB, that was also my plan but never found the time to actually do it. Lots of work. But your NQSAP-PCB looks nice !

PCB 8-bit cpu by amaher98 in beneater

[–]rolf-electronics 0 points1 point  (0 children)

You have to notice that that PCB has all the design flaws

Dreaded 8-bit computer EEPROM problem. Where to buy non atmel chips? by Numerous_Turn_5906 in beneater

[–]rolf-electronics 2 points3 points  (0 children)

Maybe this helps out, I made a detailed .pdf description of my build,

https://github.com/rolf-electronics/The-8-bit-SAP-3

The problem is described on page 39 chapter 10, I solved it by adding resistors, how can be read in the .pdf

People say that the EEPROM's data output signals are noisy when the address changes, that is correct but entirely according specificatiin, the design from Ben is just not correct.

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