Real Initial Values of RAM Registers
ATmega8 (or AVR family)
The real initial value of each RAM register whose address is from 0 to end of SRAM (excluding the I/O ones) could be any 8-bit number (a random number) after an MCU boot (after a hardware reset).
In the two MCU simulators which I know (Atmel Studio and simulIDE), the case is different. The initial value is simply set to zero instead. This may fool the writer of a code in case he forgets initializing some RAM registers. And while his code works fine when it is run by the simulator, he gets a different (chaotic) result when run in real.
For this, I suggest, if this is possible, to add an option (in MCU properties) by which the user can choose the initial value for the RAM registers to be an 8-bit number instead of ‘zero’ (the default one). There is no need to make it random. This may help a lot in debugging some codes mainly if the SLEEP instruction is used.
Any idea?
Kerim
Yes, I think it could be interesting to add an option to not clear RAM.
Personally I ussually prefer to start from a cleared RAM to see what is happening, if there are already some values I don't know if they are from this run or a previous one.
But as you mention in some cases this could lead to a diferent behavior than the real device.