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I'm intending to try a LP621024D70LL (128 KB SRAM memory, 32 pins) on an Arduino Mega.

However, I now see there is no library for it ... I wonder how hard it is to access it? I can miss 32 digital pins (the Mega has enough), however, I'm a bit worried about having to write a library, especially since I do not have any gear like an oscilloscope.

Would it be easy to use the library of the more knwn 32K256 or 23LC1024 as basis? (where I also have no experience with btw).

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That's so old I can't find a datasheet for it. If you know the pinout then you know more than me at the moment. Chances are it's a standard 8-bit CPU interface.

  • Writing:

Set the address on the address pins, set the data to write on the data pins, enable the chip, and pulse WR.

  • Reading:

Set the address on the address pins, enable the chip, and while pulsing the OE pin read the data pins.

And no, you can't really use a serial SRAM chip library as a basis - the operation is completely different.

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    allcomponents.ru/pdf/amicc/lp621024d70ll.pdf – dandavis Mar 20 '17 at 14:41
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    Yep, it is as I described. It has two chip-enable pins, one has to be high and the other low to enable it (you can probably tie them both permanently enabled since you aren't sharing the bus) and just toggle the OE or WR pins. – Majenko♦ Mar 20 '17 at 14:43
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    No one much uses parallel SRAM chips any more. They are quite rare new. – Majenko♦ Mar 20 '17 at 14:43
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    This kind of chip is best used with a small MCU. Something like a 6502 or a Z80. Use it to build your own computer from discrete ICs ;) – Majenko♦ Mar 20 '17 at 15:03
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    And many other systems too. 4 things are all you need: a 6502, some SRAM (you have), a parallel Flash chip, and some form of IO interface. Oh, and some way of getting code onto the flash chip. And there's your computer. – Majenko♦ Mar 20 '17 at 15:10

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