readSPI()

[Serial Peripheral Interface]

unsigned char readSPI();

Description

Reads data from the follower chip contained in the buffer.

Parameters

None.

Returns

The next byte from the buffer.

Example Code

The code initializes the SPI communication with the clock pin connected to pin 13, the data in pin connected to pin 12, the data out pin connected to pin 11, the chip select pin connected to pin 10, and the polarity of the chip select line set to LOW.

Continuously checks if the chip is selected, and if it is, checks if the SPI bus buffer contains any data, and if it does, reads the data from the SPI bus buffer and save it into the EEPROM.

void setup() {
    beginEEPROM(32);                // initializes the EEPROM
    beginSPI(13, 12, 11, 10, LOW);  // initializes the SPI communication with the clock pin connected to pin 13, the data in pin connected to pin 12, the data out pin connected to pin 11, the chip select pin connected to pin 10, and the polarity of the chip select line set to LOW
}

void loop() {
    if (selectedSPI()) {            // checks if the chip is selected
        if (availableSPI()) {       // checks if the SPI bus buffer contains any data
            writeEEPROM(1, readSPI()); // reads the data from the SPI bus buffer and save it into the EEPROM
        }
    }
}

Notes and Warnings

• If the function readSPI() is called when no data is available, the function will return 0.
• The function readSPI() will delete the data from the buffer after reading it, if you want to keep the data, you should store it in a variable, or call the function peekSPI() instead.
• The return value of the function readSPI() is an integer between 0 and 255 or an unsigned char.