How to access only 4 bits of microcontroller port in C

[quris_terris]

bitwise operator +microcontroller

i m using port 1 of microcontroller n want to acess only four bits at a time without disturbing other four bits. I want to do this in C language.i want method which work on four bits at a time not one by one bit.

 

[tkbits]

how to access bits in c language

On output, you fake this by setting the "undisturbed" bits to the values they already have.

 

[SphinX]

Salam,

You can do this using Bitwise operators in C such as & (and), ^ (XOR) and |(OR)

Read
https://www.gamedev.net/reference/articles/article1563.asp


Bye

 

[rajavel]

If you want to access only 4 bits at a time then do masking operation by using BITWISE operators & (Bitwise AND) | (Bitwise OR) ....

for eg var=79
to use only 4 lower bits and the original no with " 0F " .
temp = var & "0F";
similarly for upper 4 bits use " F0 "

 

[banh]

i m using port 1 of microcontroller n want to acess only four bits at a time without disturbing other four bits. I want to do this in C language.i want method which work on four bits at a time not one by one bit.

perhaps you can describe more clearly what tasks you're gonna perform on the port..

if your port is bidirectional (read+write), it is ok to read in 8bits at a time, modify your 4bits and write back 8bits.