Implementing Table Read and Write in PIC18F4550

Hi,
Anyone knows here how to implement Table Read and Write in PIC18F4550 using MPLAB-X or MPLAB IDE as the environment and C18 Compiler.

Kurenai_ryu

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you need to use the 'rom' attribute while defining your pointer and #pragma romdata if it's a table.

for example a table in flash memory (two examples, one table at 0x5000 and other at 0x5200):

#pragma romdata PRODS=0x5000 rom int Productos[]= ; #pragma romdata PRODS2=0x5200 rom char Prods[][2]=< , , , , , , , , , , , , , , , , , >; //to finnish pragma code! #pragma code

and use it like a normal table

. sb1 = Prods[3][0]; sb2 = Prods[3][1]; .. //you know, right?

if you need you can define the pointer externally as:

extern rom int Productos[]; extern rom char Prods[][2];

rom char* maPointer;

and use it as you need

. maPointer = 0x5000; //points to some part of the memory bv = (*maPointer); //read address 0x5000 . maPointer++; //now points to 0x5001; //etc . //and also . (*maPointer) = someValue; //prefills page byte, read the datasheet for actual write in memory. 

it also works with the table version!

Prods[10][0]=newValue; //prefills page byte, again please read the datasheet for actual write. even it's more complicated with a table. do it with a known pointer