Why SPI is used in Embedded C - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define SPI as a communication protocol.

Embedded C

const char* protocol = "[1]";

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AUSB

BUART

CI2C

DSPI

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing SPI with UART or I2C protocols.

SPI stands for Serial Peripheral Interface, a common communication protocol used in embedded systems.

2fill in blank

medium

Complete the code to initialize SPI clock speed.

Embedded C

SPI_InitTypeDef SPI_InitStruct;
SPI_InitStruct.ClockSpeed = [1];

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A9600

B1000000

C115200

D50000000

Attempts:

3 left

💡 Hint

Common Mistakes

Using UART baud rates instead of SPI clock speed.

SPI clock speed is often set in Hz; 1,000,000 Hz (1 MHz) is a common speed for SPI communication.

3fill in blank

hard

Fix the error in SPI data transfer function call.

Embedded C

uint8_t received = SPI_TransmitReceive([1], 0xFF);

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Abuffer

BNULL

Cdata

D0xFF

Attempts:

3 left

💡 Hint

Common Mistakes

Passing constant 0xFF instead of variable data.

The function SPI_TransmitReceive requires the data to send as the first argument, typically a variable holding the data.

4fill in blank

hard

Fill both blanks to create a dictionary of SPI pins and their functions.

Embedded C

const char* spi_pins[] = {"MOSI", "MISO", "[1]", "[2]"};

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ASCLK

BCS

CCLK

DGND

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing GND or CLK with SPI signal pins.

SCLK is the clock pin and CS is the chip select pin in SPI communication.

5fill in blank

hard

Fill all three blanks to complete the SPI data transfer loop.

Embedded C

for (int [1] = 0; [1] < [2]; [1]++) {
    buffer[[1]] = SPI_TransmitReceive(data[[1]]);
}

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Ai

Blength

Ccount

Dindex

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variables inconsistently in the loop.

The loop variable is commonly 'i', and the loop runs until 'length'. The same variable 'i' is used to index arrays.