I finally got it to work! I redid the whole assembly, but it looks like the problem was not in the assembly itself. Here is what it looks like now (Note that the ZIF is not part of the assembly and only used here to keep the IC upright for the photo):
IMG_20190406_134818.jpg
It looks like when ...

So I've been implementing the design:
IMG_20190402_193444.jpg

As you can see, I used a couple of paperclips and some electrical tape as the battery terminal, and I connected an 18k resistor to the CE/ pin as a pull-up resistor.

I can't get it to work, all information is lost when I disable the ...

If I can jump in... if you can understand how two resistances in series act as a voltage divider , you're almost there. When a driving chip pulls low, it has a finite drive, so if there's something pulling up at the same time, the supply voltage gets divided. You can approximate the driving chip as ...

The pull-up resistors are there to keep the control inputs in their false position when the 5v power fails. Pull-ups are generally chosen so that they can do their job quickly enough, but also so that they can be overwhelmed by an output driver. A CMOS output ideally shorts to Vcc or GND, depending ...

The 1N5822 diodes are silicon and the 1N60 diodes are germanium, that explains why their Vf vs. Af curves look so different.

Also, the !N5822 diodes, as Garth mentions, do have a fairly high reverse leakage current. The 1N60s are far better in this respect.

However, this PDF from Cypress does not ...

I would use a single CR2032 and a pair of Schottky diodes like the 1N60P to ensure the battery diode turned off when the 5V is applied.

The no-load voltage of a CR2032 is about 3.3V~3.4V giving you up to 6.8V total. The Vf of a 1N4001 at very low current is under 0.8V, so you might end up draining ...

If the SRAM has a low-power data-retention mode, it will work on just a couple of volts. You don't won't 5V on it for that, as the power requirement will be much higher. I show a simple circuit at http://forum.6502.org/viewtopic.php?f=4&t=573&p=32004#p32004 (although it sounds like you might not be ...

Greetings,

Recently, I've been unable to write to a 28c256 EEPROM despite my best efforts ( http://forum.6502.org/viewtopic.php?f=12&t=5584 ). Due to this, I've began looking for alternatives and my idea right now is to use a battery to maintain an SRAM chip powered while I transfer it from my ...

As an update, I've received a new 62256 and everything works perfectly. I am still unable to program the at28c256 however.

Remember that the EEPROM control signals CE & OE & Write at all active low.
When you're not running a cycle, the control signals should be inactive (=HIGH).
The general flow of an EEPROM cycle should be
1: Set up the address bus value. Set the data bus direction. Set the data bus value.
2: Toggle ...

That datasheet you're looking at isn't the same as the one I have, at least in terms of layout. I got mine from the Microchip site.
The write-protection sequences haven't changed, though, so it might not be important.

I think you just have to make sure that you write that sequence, with nothing in ...

If the EEPROM you're talking about is an Atmel/Microchip AT28C256, I've successfully disabled the software write protection before, and written to it in-circuit, but that was using an already-working 65C02 system.
I haven't made much use of that fact yet, but I have done so.

Disabling the software ...

Won't the heat damage it? No, not unless you take a LONG time to do the soldering. A fine tip on the iron is helpful. And you want it to be fairly hot so the job can be done quickly. If you have any extra/worthless IC's around you can practice soldering on them. Edit: I found a photo...
Solater ...

As for the 28c256, for a brand new chip it seems to me that any write protection would be disabled when the chip leaves the factory. Or was your chip used/surplus? In any case, I suggest you get a 2nd opinion about write protection.
The 28c256 is supposed to be brand new, it came from the same ...

Won't the heat damage it? No, not unless you take a LONG time to do the soldering. A fine tip on the iron is helpful. And you want it to be fairly hot so the job can be done quickly. If you have any extra/worthless IC's around you can practice soldering on them.

With A10 to OE, I get around 1.4 ...