EE/CE 6302 Homework #3: Interrupts and IO Name:_____________________ Student Number:_______________ 1. Why is RET is an emulated instruction but RETI is not? 2. Describe “shared data problem” in the context of interrupts. Provide a solution for example 6.10 in the MSP430 Text book. How could you prevent issues of this sort?
1. Why is RET is an emulated instruction but RETI is not?
2. Describe shared data problem in the context of interrupts.
Provide a solution for example 6.10 in the MSP430 Text book. How
could you prevent issues of this sort?
2
3. a) You are asked to create a capacitive touch sensor using
GPIO on MPS430. For capacitive touch sensors, you are to measure
the capacitance of a sensor. Note you are
asked to do this using digital peripherals NO ADC or DAC.
Describe your solution and include schematic, programs, any
information that you feel will be useful to
understand and replicate your design.
3
b) Describe the fundamental limits of your proposed solution. We
are mostly
interested to evaluate your analytical skills.
Does your solution measure the amount of pressure applied to the
sensor? How
quickly can you take the readings, i.e., from the time the
sensor is touched, how long
does it take to determine the touch event? How frequently can
you read from the
sensor? Can you discuss your answer in the context of both
high-end and low-end
array of touch sensors? Remember, an array of touch sensors can
be composed of
