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Re: Software I2C
> Unfortunatelly to bring speed to optimum we may need to write it in
> asm, so we would not need to save all registers on the stack. Or are
> there any ways to tell the compiler to save all used registers and
> not the others?
If you are writing ASM it does not matter much. Also the FIQ has half
a bank of registers of its own, ie registers R8_FIQ-R14_FIQ replace
registers R8_R14 during a FIQ. So you can destroy the FIQ registers
and not have to worry about it. Check out the ARM book "Architecture
Reference Manual", by David Jagger.
Andrew
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