AT28C16 EEPROM learning experiments

[_q12x_]

Thanks to mister @marconi , I received his chip AT28C16 gift from England !
I will start to make the 5x7 led matrix project that you did.
I will make it alone as much as I can (as usual). And I will ask you for clarifications on the way.

 

[_q12x_]

I see. I am using my proteus circuit that I built already, ofcourse but I used some other memory chip in there, if you remember. Ill have to adapt to this one here. It was good if you had already the circuit prepared and ready, but is fine without it. I will manage with what I have.
I had to do a lot of preparations, download pdfs, rename a lot of IC's pdfs in my PC, I had to make a new order in everything. And then retrieve the pinout for each IC, print them, and now hopefully assemble them all correctly.
In my original circuit simulation I used a generic FlipFlop with a D linked to /Q.
But now I am using 4027 which have K an J. Which one I should use ?

 

[_q12x_]

Some problems in the very begining...blah...

 

[_q12x_]

I figure out the 4027 toggle circuit. Now is working correctly.

 

[_q12x_]

I still have to figure what is the problem with the 7493 circuit - why is not counting binary but randomly ? It may be damaged? Is one of the thoughts that crossed my mind.

 

[marconi]

Deleted post. And some more text……

 

[_q12x_]

I built separately another circuit for 7493, (that counts to it's maximum 16 beat's)

with the same IC as before ,but also with another brand new, and I got the same random result, so the IC is good.
I also replace that big button with a brand New button and again, some slight improvement, But still not good enough.
I built in the movie, a button debouncer using 470nF, After movie, I switch to a 10uF and now to a 200uF. The difference is visible and better but still not good enough. I believe I might have to make a button debouncer using a 555.
I strongly believe is the button fault.

 

[marconi]

Please draw me your button de bouncer circuit.

 

[_q12x_]

.

 

[marconi]

The push button de bounce circuit can be just like the one for the eeprom programmer. This circuit produces a nice sharp negative going pulse when the button is pressed. The 7493 has clock inputs which are triggered by negative going transitions ie 5V to 0V.

 

[_q12x_]

Is working now...with that 555 debounce circuit...what a day !
I really wonder what's your trick that you can figure out so quickly the sequence of the 7493? And not using a simulator like I do. If you can explain your process in words will be more than good.
You are right, indeed it counted LESS than 7, now that I can actually have a clear button press, without any monkey bizniz. I know in my simulation I did it right.. but I have to recheck it now.

 

[marconi]

Home - BBC News - https://www.bbc.co.uk/news

As friends of the United Kingdom I thought you and Romania might like to look at some of the television coverage of the funeral of our late dear Queen Elizabeth. Most of today many (millions!) have been watching the television and listening to the commentaries, music and prayers - very moving and a glorious way to mark Her Majesty's passing. I hope you gain a sense of how loved and admired she was by ' the great and the low'

 

[_q12x_]

• I was having today a strange feeling about UK queen funeral... without watching any news, because I was working all day long like a slave. I had a brief feeling at some point. Strange things are transmitted, even feelings.
• Indeed, Romania is transmitting to England it's sincere condolence and we are sharing a tear along with you with a piece of broken hearth as well.

 

[_q12x_]

If you are not in the mood, this can be watched another day, so no problem.
I am posting my progress so far.
And I am thinking on a solution for the count to 7 problem. Again, what a day....

 

[marconi]

deleted too few words etcetera

 

[marconi]

View attachment 101731.

For increased reliability of operation:

1. Connect a 0.01uF capacitor between 5 and 1.
2. Connect a 0.1uF in parallel with a 1uF electrolytic between 8 and 1.

Is the pushbutton 'normally closed' as you have drawn?