Pic16F628A and 24LC256 EEPROM I2C

[Melanie]

1. Remove R22... connect directly to Vdd/+5v.

2. Remove R23 & R24, connect directly to Vss/0v.

3. Value of 10K is too high for R25 & R26. Drop it to 4K7.

Merry Christmas (or Happy Holidays - whichever you prefer) to all...

[Mike96]

Found problem with a connection to the 24LC256 chip.

Apperently, the connection to the SCL (clock) line was not making contact to Pin 6 of the chips. After getting the connection to then, the circuit worked flawlessly.

Originally my story was that I used to use the PIC16F628A internal EEPROM memory, but when a new chip was inserted (programmed ), the count was lost.

So finally I relized that external Ram was the key.

Hooking up the 24LC256 in a SOIC package, I used the wrong connection (unused wire) to put pull-up on clock signal. After connecting the proper line to the chips, the circuit worked.

Here is a complete program and schematic for 24LC256:

See Attachments

Thank You

[Mike96]

I do not know the 24LC515 chip but post your PIC BASIC text file and I will look at it to see where your error might be.

I need to know what is your clock frequency and PIC Chip Type ( 16FXXX ).