Qualcomm Interview Question

Programming Related: * what is the keyword volatile, static, const do? * where do static data reside in memory? * What are some ways to pass data into a function? and what the advantage and disadvantages? O/S Related * What makes an OS real time? * Difference between Semaphore, Mutex, and spin locks? * What is priority inversion, and what are methods to avoid it? * If processor has a FP unit, is it ok to use FP inside kerenel? why/why not? * What is is the difference between Non-blocking vs blocking calls? What are the benefits of each? * How would you execute a non-blocking call in kernel? Debuggin Related: * What is stack trace? * What data get pushed into a stack when jumping into a function call? * Give some example you would use a scope to trouble shoot software problem? What line would you use to trigger the scope? I/O Interface Related: * Explain UART communication protocol? * What signals are connected to DB9 connector, and how are they beeing used? * What are some ways UART could have communication error? * Explain I2C Communication protocol. How the Start, Stop condition generated? How do you select which device to communicate when all the devices tight to gether? * Explain SPI Communications.