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Altera_Forum's avatar
Altera_Forum
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21 years ago

I have a problem with printf

i use a cyclone the hardware is construct and run already on my prototype if i use the instruction printf on debug mode my hardware stop to run and i can't find why have you one idea?
Altera_Forum's avatar
Altera_Forum
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21 years ago

A little more information about the problem would help. For example, are you running in an OS environment? Are you trying to print from an interrupt. Does any of the print get printed?

If you are using the uC/OS-II environment and trying to print, the software buffers are relatively small and when the buffer is full the system waits for the interrupt service routine to fire indicating that more characters can be written to the hardware. Then an event flag is used to signal the task that it is okay to transmit. If this happens in a condition when the OS is not running, from interrupts or when interrupts are locked, or the tasking hasn't started it causes a deadlock. (This happens because the flag and semaphore error codes are not monitored in Altera's UART driver.)