RE: [avr-gcc-list] assembler expressions

[Ben Mann]

Why doesn't this work?

#define F_CPU 18432000
#define F1 20000
#define F2 20001
#define LO_F (unsigned long) ( (float) F1 *  F_CPU / (15*16777216) )
#define HI_F (unsigned long) ( (float) F2 *  F_CPU / (15*16777216) )
...
  ldi  r21,lo8(LO_F)
  ldi  r22,hi8(LO_F)
  ldi  r23,hi8(LO_F)
??

I have used code like this in the past with no problems.
I don't know what the implications of (float) are though.

Regards

Ben Mann

-----Original Message-----
.equ LO_F,  F1 * F_CPU/(15*16777216)
.equ HI_F,  F2 * F_CPU/(15*16777216)