Hello,
on AVR I have some assemebly sections in order to speed things up in an interrupt service routine. On each interrupt call a counter is incremented. This counter I would like to keep in a register instead of in a variable. Is there any chance to do that? I.e. the register has to be reserved so that the compiler never uses it, so its preserved between my inline assembler calls. Or, even better would be if its possible to define a global variable to be kept as register. On AVR controllers there are 30 registers, so some reserved registers wouldn't hurt. The interrupt in my application will be called every 100 clock cycles, so the loads and stores to memory do make a difference.
Regards