piclist 2001\07\11\134111a >
Thread: correct typecast to pass pointers in Hitech C
face BY : mike@.....whitewing.co.uk

>>readeeprom(rxbuffer[2],8,&rxbuffer[0]);                <---- this should work,
>if rxbuffer is an
>                                                       array of char
it DOES work, and also works for non-array variables, but the compiler
thinks I'm doing something wrong.

>>readeeprom(rxbuffer[2],8,(char)&rxbuffer[0]);   <---- this is wrong, you
>don't want to cast
>                                                       the pointer to char!
But a pointer IS a char (i.e. byte) on a pic! I know it, but the
compiler doesn't seem to trust me!

>readeeprom(rxbuffer[2],8,(char *) &rxbuffer[0]); <---- this is correct, but
>I don't know why  you would want to
>write it this way!

I think this is what I was looking for.
There is a  VERY good reason why I want to do it this way - maybe I
shouldn't have confused things by using an array as the example!

I want to pass the address of a target variable of ANY type, so my
readeeprom routine can stuff the data straight into the  variable,
whether it be a char, int, long or array.
This is much more code, space and time-efficient than passing the
values  e.g. :
char c;
int i;
long l;
char buffer[8];

readeeprom(0,1,(char*)&c); // reads 1 byte to a char
readeeprom(1,2,(char*)&i); // reads 2 bytes to an int
readeeprom(3,4,(char*)&l); // reads 4 bytes to a long
readeeprom(7,6,(char*)&rxbuffer[2]); //reads 6 bytes to rxbuffer[2..7]

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Subject (change) correct typecast to pass pointers in Hitech C

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