Reading/writing register using macros in a single line in C

[shaikss]

Hi,

I want to read/write a register using C.
Its easy by using pointers.
But read/write by using macros in a single line.
Just by using a single line without pointers, it has to read/write the value from the register.
Can you pls help me..........

Thanks
Shabana

 

[rajeshkumar123]

Re: Help in C

Hi,

Define a macro with the address of the SFR. and use the macro name when u read and write to a register

 

[shaikss]

Re: Help in C

For example One of the register is located at location 0xFFFF0000.
I want to write 0xFFFFF into the register.
Can u tell me the sample code for this.

 

[ssss959]

Re: Help in C

with out pointer we cannot do

 

[rajeshkumar123]

Re: Help in C

#define SFR1 0xFFFF0000


SFR1=0xFFFF;

I think this will work

 

[echo47]

Help in C

Assuming the register is 16 bits wide, and your compiler's short integer is 16 bits wide:

*(volatile short*)0xFFFF0000 = 0xFFFF;

 

[kiprono]

Re: Help in C

With register level programming you have to learn pointers

 

[davidgrm]

Re: Help in C

Depends on the compiler. Some like Keil allow you to assign a variable to an address and then you can just use that variable

 

[maggots]

Help in C

yuuup just define them...

 

[vinseth]

Help in C

This should work...

#define RegisterName (*((volatile unsigned long *) 0xFFFF0000))

RegisterName = 0x000FFFFF;