Preloading data in I2C EEPROM

Is there an "easy" way to preload data into an 24LC256? I want to put about 3kB worth of ASCII data into one. I can only think of two ways:
1. Make a purpose-built circuit incorporating a PICAXE and a keyboard or...
2. Load the data one block at a time using 12 separate PICAXE programs each incorporating table commands with different data sets.

-Steve

If you are using an X2 chip (also X1?), use one of the 'slots' to provide for just this function. This feasible for you? Just an idea, as I haven't used Xx chips yet.

I'm making the assumption that your finished project will have a PICaxe reading data from the LC256.

1 - Build the project hardware.

2 - Load some temporary PICaxe code to read from a serial input, and write the data to the LC256 a byte at a time.

3 - Send the ASCII from a serial port on a PC, or similar.

4 - When you have all the data in the LC256, re-programme the PICaxe with the required project code.

The serial input could be a spare input pin, or re-purpose one just for the loading phase.

This way you could load the full LC256, or any other size I2C EEPROM, using a PICaxe of any size, even an O8.

Buzby said:

This way you could load the full LC256, or any other size I2C EEPROM, using a PICaxe of any size, even an O8.

Click to expand...

I2C on a 08??

Buzby said:

This way you could load the full LC256, or any other size I2C EEPROM, using a PICaxe of any size, even an O8.

Click to expand...

Yahoo, is there an 08M2 or 08X2 coming out shortly

Steve Widmark said:

Is there an "easy" way to preload data into an 24LC256? I want to put about 3kB worth of ASCII data into one.

-Steve

Click to expand...

@Steve,

Have a look at the code I wrote for a 40X1 in Post 14 here:
http://www.picaxeforum.co.uk/showthread.php?t=10014&page=2

You should be able to load at least 8 blocks/pages of data at a time.

Beware the paging system when writing and reading from EEPROMs.
You should read the datsheet for the 24LC256.

@Mpep,

http://www.picaxeforum.co.uk/showthread.php?p=45143&highlight=bit+bang+i2c#post45143

http://www.picaxeforum.co.uk/showpost.php?p=119651&postcount=42

These two links show the general principal.
The 18X code pokes to the tri-state registers. I don't think this can be done on an 08, so some kind of diode + pullup resistor would be needed to replicate the effect. Just using a pullup, then switching pins between 'input' and '0 level output' would have the same effect, but with horrendous code.

As Hippy pointed out in one of the linked posts, I2C on an 08 is possible, but it needs a lot of work !.

@Buzby,

Thanks for those 2 links. Hadn't seen those.

MPep.

If you need to do this more than once with different sized EEPROMs you might want to look at the PONYPROG software and interface. This would give you the ability to program a number of different types of EEProms from a PC. It might be helpful if you don't know exactly what data you need to preload or want to try variations on the data set. The software works very well and the interface is fairly simple.

Rick

Thanks guys, you've given me a lot to chew on.

-Steve