AT28C64, 28C64 Datasheet, 28C64 64K ns Parallel PLCC EEPROM Datasheet, buy 28C 28C64 datasheet, 28C64 pdf, 28C64 data sheet, datasheet, data sheet, pdf, Atmel, 64K 8K x 8 CMOS E2PROM. 28C64 64K (8K x 8) CMOS E2prom with Page Write and Software Data Protection Features. Fast Read Access Time ns Automatic Page Write Operation.
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PeterJ 16k 20 42 Here is my code, sorry if it daatasheet too cluttered: Mar 27 ’13 at Sign up using Facebook. I have tested an earlier version of the above program with a static RAM chip and everything works great. Thanks for the response, supercat. Home Questions Tags Users Unanswered.
I am using the Xicor 28C64AP chip datasheet. If it has, you’ll need to wire up all your address wires in order to disable it. Since I am only using the first three address dztasheet, the rest are tied low. That will make the remainder of your code much more readable.
One thing that is missing is on page 7 of the datasheet, it states that you need datasheft write a sequence of codes to disable write-protection. All behave the same. I have edited my question. The same diagram shows CE being asserted followed by OE for a read cycle.
Post as a guest Name. The device has 13 address pins, which should specify an address in binary from 0x to 0x1FFF. You datasheeh not indicated that you are doing adtasheet with them? Also, I would suggest that you should write a writebyte procedure which sets all address and data wires to output and puts proper values on them, ensures WE and OE are deasserted, asserts CE, asserts and release 28c46, and releases CE, and a readbyte procedure which sets all address wires to output and puts proper values on dafasheet, sets all data wires to input, asserts CE and OE, samples all the data wires, and releases CE and OE.
I added ms delays between every control pin change and made sure the order was consistent with the datasheet, but still no luck. The timings for this particular EEPROM aren’t super-critical, but it has a timer which starts when the first byte is written and gets reset if another byte is written before it expires. BTW, if the chips are equipment pulls as opposed to new parts, it’s possible that the “software protection” feature has previously been enabled.
Looking at the datasheet on page 12 it shows a timing satasheet and Chip Enable Access Time can be up to nS. The chips are new, and I actually have two from two different manufacturers. I’d recommend following that same sequence and also change your write sequence to follow the diagram on the following page. That might help things. I have tied the top 10 address bits low and am only using the first 3 for now.
I wrote a program for the Arduino Uno that writes data to the first 4 datashret and then reads the data back. Initializing pins for write