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I want to get an idea of how to use a chip, code it and burn it. So an and gate could be a good choice.

I've thought about using AT27C01024-70PU or AT89LP4052-20PU.

Got this burner in mind: https://www.batronix.com/shop/programmer/BX32P/index.html

I've already used Arduino for a bit.

Could this work?

Thanks in advance for tips and advisement.

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    \$\begingroup\$ The AT27C01024 is an EEPROM while the AT89LP4052 is a microcontroller - very different parts. \$\endgroup\$ Nov 17, 2019 at 23:02
  • \$\begingroup\$ I think he meant AT27C1024 - 1Mb 64k x 16, vs. AT27C4096 - 4Mb 256k x 16 EEPROM. Which is actually nice, because it has 16 bit data output. And I like that choice, I wish I could get them here, they have 16 output lines, much better than the 2k x 8 bit EEPROMs that I am stuck with right now. Another nice thing about them is they have well organized pins, good for circuit layout. Address lines on top, data lines on the bottom. No weird cross-overs between the sides. \$\endgroup\$ Nov 18, 2019 at 3:49
  • \$\begingroup\$ Oops, but now I see the problem with this choice: those are "One-time Programmable Read-only Memory". That's a big problem as you have only one shot at them, can't erase and re-program! Better update my answer to warn him. \$\endgroup\$ Nov 18, 2019 at 3:57
  • \$\begingroup\$ This is more or less the "old way" of doing things, using a ROM chip as a lookup table to drive a state machine. A small CPLD will almost certainly be cheaper and more flexible. I would recommend looking into the CoolRunner-II and Max V families. There are also older PAL chips such as the 16V8 and 22V10, but these tend to be more difficult to obtain/program/use. \$\endgroup\$ Nov 18, 2019 at 4:22

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Yes it can work. You want to use an EEPROM to encode complex logic. Now if all you want to try out is an AND gate, you will use only about 2 of the over 10 address lines of your EEPROM and only one of the data output lines. That is of course overkill. But it will work.

HOWEVER, WARNING, BEWARE: the AT27C1024 and AT27C4096 are One-time Programmable Read-only Memory, it's a simple PROM, not EPROM, not EEPROM. You only have one shot. This is not good for experimenting at all! Only good for mass production. And not even for many mass produced applications as you couldn't ever field upgrade your logic (firmware flash impossible!).

Stick to EEPROMs for experimenting.

Better use 28C16, 28C64, 28C256, or 28C512. Sadly they only have 8 bit of output, not 16 bit of the PROMs that you chose.

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  • \$\begingroup\$ So the EPROM I think it's called, cant do this? \$\endgroup\$
    – Lutherion
    Nov 17, 2019 at 21:52
  • \$\begingroup\$ Like I said, it can do this! Of course it can. This and a lot more than this! That 4k EEPROM can act as a complex logic gate with 12 inputs and 8 outputs. And if you hook up more of them in parallel, you can have any multiple of 8 outputs and 12 inputs. But it's a waste to use it for one AND gate only. If you want to play with chips, do some activities with 7400 TTL chips, lots of fun things to do. And you can use the EEPROM when you get to the point of actual complex logic. As for programming, you can use the Arduino Nano on a bread board with 2 74HC595 shift registers for way cheaper. \$\endgroup\$ Nov 17, 2019 at 22:29
  • \$\begingroup\$ Re, "if you hook up more of them in parallel,..." That claim could be very misleading to a newbie. "Hooking up" two eeproms that each have N address lines and M data lines, "in parallel" will give you only a tiny, fraction of the capabilities that you would get from a single EEPROM having 2N address lines and 2M data lines. Two chips with 12 address lines and 8 data lines each gives you a total of 32K of programmable bits. One chip with 24 address lines and 16 data lines would have 64 megabits. \$\endgroup\$ Nov 17, 2019 at 23:52
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    \$\begingroup\$ OK, I was not entirely sure of what you meant by, "hook them up in parallel." You meant, to get more outputs with the same number of inputs. That's easy. That makes sense. More inputs on the other hand, is not so simple. That's were I thought that your answer might mislead a newbie. \$\endgroup\$ Nov 18, 2019 at 2:16
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    \$\begingroup\$ I guess Gunter is making the Ben Eater breadboard computer. It's a lot of fun, but a lot of troubleshooting too. Check out the YouTube videos if anyone wants to see how easily an absolute mess of ANDs and ORs get elimated and replaced with two easy-to-work-with 28C16's. \$\endgroup\$
    – user233390
    Nov 18, 2019 at 8:39

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