Stupid array question

[RUBiksCUbe]

I'm working on an LED matrix project that involves displaying data on an 8 x 80 LED matrix (multiplexed of course). I was planning on storing the data to be displayed in hex form in my PIC18F252s EEPROM, which I would then be able to look at using .Bit0 or .Bit1 to see if an LED needs to be on (for example, $AA in binary is 10101010, which would mean that every other LED is on). The only problem with this plan is that the EEPROM on the 18F252 is only 256 bytes, leaving room for less than 125 rows of LEDs, which just isn't enough.

If anyone knows a good way to somehow compress data, that might be usefull, but I was thinking about storing the display data in arrays, that way I could easily switch between different messages.

So, the real question now:
Is there any way to store a bunch of data in an array on one line?

In java you can do this:
Int[] test = {5, 6, 7};

Can you do anything like that in PBP? It would make coding much easier, as opposed to going like this:
message[0] = $AA
message[1] = $2C
message[2] = $4D

and so on...

[sayzer]

.... switch between different messages.
....

Will the "different messages" come from an external source or there will be a fixed pattern inside the program and once the PIC is programmed then that fixed pattern will never be changed?



--------

[paul borgmeier]

As Sayzer is hinting, if your data does not change after you do the initial programming, you could use the LOOKUP or LOOKUP2 command. (or just the READCODE command referenced below if you preloaded your data)

If your data is going to change, you could use WRITECODE and READCODE. Also see: http://www.picbasic.co.uk/forum/showthread.php?t=137 for reference

[RUBiksCUbe]

The READCODE command actually looks perfect for me. Thanks for pointing that out.

The PIC will switch between different messages when external buttons are pushed.

[RUBiksCUbe]

Well, it was too good to be true. Whenever I compile with this in my project:

Asm
CODE 1400
DB 0
DB 220
DB 476
DB 384
DB 384
DB 476
DB 220
DB 0
DB 999
Endasm

I get some nice errors:

Found directive in column 1. (CODE)
Directive only allowed when creating an object file
Found directive in column 1. (DB)
Argument out of range. Least significant bits used.

There are 15 errors total, but they're all just copies of those 4.

Am I missing something?

[paul borgmeier]

You need to indent your program like that below. However, I believe DB is used for bytes only and you must use packing to place the word (i.e., DB 476 will not do what you want)? Others with more 16 bit processor Assembly experience might be able to offer a (better) solution in ASM.

You might want to consider using PBP's WRITECODE instead of the ASM for the initial write. Look here http://www.picbasic.co.uk/forum/show...ight=writecode and also search “WRITECODE” on this forum for examples of how to write to the 18F family, which is not as straight forward as one might think.

Asm
     CODE 1400
     DB 0
     DB 220
     DB 476
     DB 384
     DB 384
     DB 476
     DB 220
     DB 0
     DB 999
Endasm

Good Luck

edit: or consider LOOKUP2 tables