I2C vs SPI decision matrix in Embedded C - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to initialize an I2C communication with the correct clock speed.

Embedded C

I2C_Init([1]);

Drag options to blanks, or click blank then click option'

A100000

B500000

C1000000

D2000000

Attempts:

3 left

💡 Hint

Common Mistakes

Using SPI clock speeds instead of I2C speeds.

The standard I2C clock speed is 100 kHz, so 100000 is the correct value to initialize the I2C bus.

2fill in blank

medium

Complete the code to select the SPI mode that supports full-duplex communication.

Embedded C

SPI_SetMode([1]);

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ASPI_MODE_0

BSPI_MODE_1

CSPI_MODE_2

DSPI_MODE_3

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing SPI modes with half-duplex modes.

All SPI modes support full-duplex communication, but SPI_MODE_0 is the most commonly used and simplest mode.

3fill in blank

hard

Fix the error in the code to correctly read a byte from an I2C device.

Embedded C

uint8_t data = I2C_ReadByte([1]);

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Agpio_pin

Bspi_channel

Cdevice_address

Dbaud_rate

Attempts:

3 left

💡 Hint

Common Mistakes

Passing SPI channel or GPIO pin instead of device address.

The I2C_ReadByte function requires the device address to read data from the correct device on the bus.

4fill in blank

hard

Fill both blanks to create a decision matrix entry for choosing SPI over I2C.

Embedded C

if (speed > [1] && devices > [2]) {
    use_spi = true;
}

Drag options to blanks, or click blank then click option'

A400000

B5

C10

D100000

Attempts:

3 left

💡 Hint

Common Mistakes

Using I2C speed values or wrong device count.

SPI is preferred when speed is greater than 400 kHz and the number of devices is more than 5.

5fill in blank

hard

Fill all three blanks to complete the function that decides between I2C and SPI based on speed, device count, and wiring complexity.

Embedded C

bool choose_spi(int speed, int devices, int wiring_complexity) {
    if (speed > [1] && devices > [2] && wiring_complexity < [3]) {
        return true;
    } else {
        return false;
    }
}

Drag options to blanks, or click blank then click option'

A400000

B3

C10

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing device count and wiring complexity values.

The function returns true for SPI if speed is above 400 kHz, devices are more than 5, and wiring complexity is less than 10.