Dealing with large amounts of data on the PIC

[wackazong]

Hi,

I have a project for a MBHP that needs to store some data (about 4kB) in the memory of the PIC. I am using the PIC18F4685, therefore I should have enought memory. What is the best way to organise this memory? I know that you cannot use arrays that are bigger than 256 bytes, therefore I am thinking of using multiple arrays of 256 bytes (16 for 4kB). Is there a more convenient way? May using short assembler parts which access the memory? Any ideas?

I am storing the I2C addresses of 48 LED drivers, the corresponding LED addresses on these drivers, and the LED state (256-step indiviual PWM) for each LED (in total 3*256 LEDs). Storing all this on the PIC makes the interface to the computer so much easier and faster.

Thanks, ALEXander.

[wackazong]

Let me reply to myself:

4kB is too much for the data memory, it is only roughly 3kB. And the EEProm is only 1kB (I was just fixed on the 96kB program memory)...

So I have the choice between Bankstick or access to the Flash Memory. Which one ist faster? I should have plenty of free flash available in the PIC18F4685, or shouldn't I? If yes, which address could I use to store my 4kB?

Many thanks, ALEXander.

[TK.]

Yes, in this particular case it makes sense to store tables in internal flash. Your questions don't make clear if you want to replace the data tables dynamically (uploading a new table without touching the code). I guess, that this isn't required for your application.

So, let the linker locate the data tables - don't take care for the absolute addresses by yourself, this isn't really required.

Best Regards, Thorsten.

[wackazong]

Yes, thats how I will do it. Thanks.

ALEXander.