Hi i want to get the value of the carry flag (after shift to left) from c code how to do it?? thanks
i want to get the value of the carry flag (after shift to left) from c code how to do it??
The CY bit should be defined in your processor-specific .h file.
However:
Don't do it. Messing around with registers in C is a good way to create a maintenance and debugging nightmare. There is no specified way that these registers behave in C.
Write a short assembly routine that does what you're trying to accomplish and call it from C. This is the clean way to do it.
As Christoph says, it is possible - but definitely not advisable.
Sure, you can access the CY flag in 'C' - but you can never be sure that it relates to the operation that you think and/or require...
The only safe way, as Christoph says, is to use assembler and call it from 'C'.
i want to get the value of the carry flag (after shift to left) from c code one answver The only safe way, as Christoph says, is to use assembler and call it from 'C'.
in C, the same is possible, but by other means:
bit flag;
flag = 0; if (var &0x80) flag = 1; var <<= 1;
use 'flag' as you would CY
Erik
the trigger to use the carry is to remove the "if" ...
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