Don't ever divide by zero on AVR atmega32!
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PraveenAlexis
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Don't ever divide by zero on AVR atmega32!
[media]http://www.youtube.com/watch?v=mZ7pUADo ... r_embedded[/media]
Re: Don't ever divide by zero on AVR atmega32!
The reason I think is that the microcontroller becomes uncontrollable after such illegal operation that will lead to unexpected behaviours such as ON/OFF pins, Input/Output state of ports, etc... Just imagine a Port (or a Pin) which was configured to work as an input, become an output as a result of an illegal operation. Usually after such illegal operation, your code no longer has control over the microcontroller. When you become a professional in programming, you will easily identify the possible lines of code which can lead to an illegal operation.
Stack Overflow is another tricky problem. Stack is used for many things. More importantly to backup registers at the time of procedure call. After the call is done, registers are restored so that the calling function can continue from it's last state. When you call lots of functions within a single function (good example is recursion), then the requirement for stack become high. However Stack is a hardware implementation so it is limited mostly to a specific amount of memory. So calling lots of functions will make the CPU to go Stack Overflow which will make the CPU uncontrollable.
So it is not only Atmel, all other processors also have a chance to blow off with these illegal operations (mostly due to the way you wired it).
Here is an example: Don't ever allow to stack overflow on AVR Atmega88V.
[media]http://www.youtube.com/watch?v=4YEL7Jx26Wk[/media]
Stack Overflow is another tricky problem. Stack is used for many things. More importantly to backup registers at the time of procedure call. After the call is done, registers are restored so that the calling function can continue from it's last state. When you call lots of functions within a single function (good example is recursion), then the requirement for stack become high. However Stack is a hardware implementation so it is limited mostly to a specific amount of memory. So calling lots of functions will make the CPU to go Stack Overflow which will make the CPU uncontrollable.
So it is not only Atmel, all other processors also have a chance to blow off with these illegal operations (mostly due to the way you wired it).
Here is an example: Don't ever allow to stack overflow on AVR Atmega88V.
[media]http://www.youtube.com/watch?v=4YEL7Jx26Wk[/media]