A function pointer 10 Why is the scheduler moved into the TimerISR function The

A function pointer 10 why is the scheduler moved into

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A function pointer. 10 . Why is the scheduler moved into the TimerISR function? The scheduler is moved so that you can put the system to sleep when it’s not processing. Chapter 7 Outline 7.1 Pulse Width Modulation Signal B0 is a periodic signal because the pattern repeats, in this case with a period of 1 second. The duty cycle is the percentage of time the signal is high during the period. o duty cycle = H / (H + L) A signal with a duty cycle of 50% is called a square wave . A pulse width modulator or PWM is a programmable component that generates pulses to achieve a specified period and duty cycle. o PWM can be captured as a synchSM and implemented in C on a microcontroller. o On the average, a PWM's output, in terms of energy, is equivalent to the output's duty cycle. One use of a PWM is to control a DC motor. Another use of a PWM is to generate a tone on a speaker. 7.2 UARTs A microcontroller task may need to communicate data with another physical device such as a liquid crystal display or another microcontroller. a hardware device, called a UART , that automatically transmits eights bits of data serially, meaning one bit at a time, over a single pin. o Universal asynchronous receiver/transmitter. o Receive is typically written as rx and transmit as tx. The UART must first be activated by the RIMS built-in function UARTOn(). 2
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Homework 9Z8 o To transmit data, a program writes to a special global variable T of type unsigned char. Upon being written, the contents of T will be shifted out serially over the tx pin.
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