Accessing Multiple SFR Register Bits

[roys29]

Is it possible to create a variable that has 8 bits (byte?) so that each bit accesses a different SFR register bit? For example, I want to access PORTA bits 0-3 and PORTB bits 0-3. So, if I set the variable to %00010001 RA0 and RB0 would set. I know I could do it with a subroutine by passing a byte variable and setting the appropriate register bits, but I just wonder if there is an easy way? Thanks in advance for your help.

[filip]

Hi,

You can do this using bit fields/union if I'm correct.

Regards,
Filip.

[roys29]

I'm not sure how the union works. Can you give me an example? Thanks.

[Soumitrab]

Lets say your var is X (byte / unsigned int)
so the easiest way is

Code: Select all

X.B0 := PORTA.B0
...X.B3 := PORTA.B3
X.B4 := PORTB.B0
...X.B7 := PORTB.B3