How does this code work?

[viknes1985]

Can anyone tell me, how this code is run?

[dyeatman]

...

[FvM]

Although the both codes use a similar 8-Byte-shift/rotate block, they have apparently different purpose. The first is a receiver shift register, the second does a rotate of a data rather than reading from an input. The first is intended for ISR operation, the second isn't.

[Ttelmah]

Let me make a 'comment' purely on nomenclature.
#define MASK_INPUT 0x10

Is a 'macro'.
The line:
CARRY = (datas & MASK_INPUT)? 0:1;

Is a 'conditional statement'.
It sets the variable (definition not shown, but presumably an equivalent to the CCS '#bit' definition, addressing the processor carry bit), to either '0' or '1', according to the value of the selected bit in datas.

Then the rotations are done, with the carry bit being moved into the first bit of the data block.

Best Wishes

[viknes1985]

Thanks Ttelmah and FvM. You're right FvM, the posted code is to get the input from the device. What i don't understand is, whenever the rotation of the arrays takes place, how does the nearby arrays affected.....


Thanks again

[FvM]

I guess, you mean how the shifted out bit is transferred to the next register?. The instruction does rotate left through carry. Simply consult the description of RLF instruction an a PIC16xxx reference manual.