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Master Out Slave In (MOSI)

maker

MOSI is a unidirectional communication line used in SPI communication protocols for transmitting data from the master to the slave device.

expanded

In the Serial Peripheral Interface (SPI) protocol, the Master Out Slave In (MOSI) line is utilized for carrying data signals from a master device to one or more slave devices. This communication is vital in applications where data needs to be precisely controlled and sequenced, such as in microcontroller-based systems interfacing with a wide range of peripherals such as sensors, displays, and memory modules.

examples

In a microcontroller system using an STM32F4 series board communicating with an MCP2515 CAN Controller, the MOSI line is used to send configuration and data packets from the STM32F4 master to the MCP2515 slave.

This configuration is commonly used in automotive applications where microcontrollers need to send configuration commands to CAN controllers to interface with vehicle buses.

A Raspberry Pi 4 Model B uses the MOSI line to send image data to an ILI9341-based TFT display module.

This configuration is typically used in embedded systems where a Raspberry Pi acts as a central unit controlling graphical displays for user interfaces.

related terms

Master In Slave Out (MISO)
MISO is a communication line used in SPI protocol to transfer data from the slave device to the master device.
Serial Peripheral Interface (SPI)
Serial Peripheral Interface (SPI) is a synchronous serial communication protocol used for short-distance communication, primarily in embedded systems.
Slave Select (SS)
SS is a digital signal line used for enabling a slave device in SPI communication.
Serial Clock (SCK)
A serial clock (SCK) is a timing signal used to synchronize communication between devices in a serial communication interface.
Inter-Integrated Circuit (I2C)
I2C is a multi-master, multi-slave, packet-switched, single-ended, serial communication bus.