Clock gating for power saving in Embedded C - Mini Project: Build & Apply

Clock gating for power saving

📖 Scenario: In embedded systems, saving power is very important. One way to save power is to stop the clock signal to parts of the circuit that are not in use. This is called clock gating. In this project, you will write simple C code to control clock gating for two peripherals: a timer and a UART.

🎯 Goal: You will create variables to represent clock enable signals for the timer and UART. Then you will write code to turn these clocks on or off based on whether the peripherals are needed. Finally, you will print the clock status to see if clock gating is working.

📋 What You'll Learn

Create two variables to represent clock enable signals for timer and UART

Create a configuration variable to decide if UART is needed

Write code to enable timer clock always and enable UART clock only if needed

Print the status of timer and UART clock enable signals

💡 Why This Matters

🌍 Real World

Clock gating is used in real embedded devices like microcontrollers and SoCs to save battery life by stopping clocks to unused parts.

💼 Career

Understanding clock gating helps embedded engineers optimize power consumption in hardware designs and firmware.

1

Create clock enable variables

Create two integer variables called timer_clk_enable and uart_clk_enable. Set both to 0 initially to represent clocks off.

Embedded C

// Create two integer variables called timer_clk_enable and uart_clk_enable and set both to 0
// Your code here

Need a hint?

Use int to create variables and set them to 0.

2

Create UART needed configuration variable

Create an integer variable called uart_needed and set it to 1 to mean UART is needed.

Embedded C

int timer_clk_enable = 0;
int uart_clk_enable = 0;

// Create an integer variable uart_needed and set it to 1
// Your code here

Need a hint?

Use int uart_needed = 1; to create the variable.

3

Enable clocks based on configuration

Set timer_clk_enable to 1 to always enable timer clock. Use an if statement to set uart_clk_enable to 1 only if uart_needed is 1. Otherwise, set uart_clk_enable to 0.

Embedded C

int timer_clk_enable = 0;
int uart_clk_enable = 0;
int uart_needed = 1;

// Enable timer clock
// Enable UART clock only if uart_needed is 1
// Your code here

Need a hint?

Use if (uart_needed == 1) to check the condition and set uart_clk_enable accordingly.

4

Print clock enable status

Use printf to print the values of timer_clk_enable and uart_clk_enable in the format: "Timer clock: %d, UART clock: %d\n".

Embedded C

int timer_clk_enable = 0;
int uart_clk_enable = 0;
int uart_needed = 1;

timer_clk_enable = 1;
if (uart_needed == 1) {
    uart_clk_enable = 1;
} else {
    uart_clk_enable = 0;
}

// Print the clock enable status
// Your code here

Need a hint?

Use printf("Timer clock: %d, UART clock: %d\n", timer_clk_enable, uart_clk_enable); inside main.