Thanks Darrel,
I had mis-read the manual and assumed that the compiler took care of the stepping by 2 bytes. I was aware of the 4 blocks, and planned to break my data into 128 word chunks for fit into each block.

I tried your revised code and the LCD shows a correct read-back, but when I read the EEPROM in my PROM reader all I get is the 1st 3 bytes changed and the rest remains FF.
It's as if the address increment is not working and I'm just overwriting the same data. I just can't see why that would happen.

I have checked the hardware over carefully - not much to screw up there. Data and clock are pulled up with 10K and the WP line (pin 7) is wired to GND. Power is good, filtered, clean 5V. Signals all look "textbook".



[QUOTE=Darrel Taylor;91895]tekart,

With the 24LC08, the address needs to be a BYTE.
There are also 4 "blocks" of 256 bytes that can be selected in the "control" byte.
And the address should increment (STEP) by 2 for word sized data.