STM32L4 Bare-Metal Peripheral Drivers Development

Explore GPA basics, including pins organized into ports and alternate functions. Review the direction and data registers, HP and APB buses and RC, crystal, PLL.

Develop a GPIO output driver by leveraging ST's pre-defined register headers, downloading the sdm32l4 package, and integrating the device header to configure registers efficiently.

Explore controlling STM32L4 GPIO outputs with the bit set/reset register (BSRR), using set and reset operations to blink a LED via specific pin bits.

Develop a GPIO input driver for the stm32l4 board by enabling GPIOC clock, configuring PC13 as input, and reading the IDR bit 13 to detect an active-low push button.

Master the uart protocol basics, serial vs parallel, synchronous versus asynchronous transmission, framing with start and stop bits, baud rate, parity, and word length.

Develop and test a uart transmitter driver by implementing modular usart write function that waits for the transmit data register to be empty, then writes to tdr, with realterm verification.

Retarget printf for the stm32l4 by implementing the UTX driver's _putchar function, copy and adapt the project, build it, and verify serial output on the board.

Modularize the uart tx driver by separating it into its own files, exposing only the necessary function, and including the header in the main program.

Develop a UART receiver driver for STM32L4 by adapting project, enabling PA3 as AF7, and implementing a read function that waits for the receive data register and returns the byte.

Test the UART receiver driver on STM32L4 bare-metal by enabling clock access, configuring output pins, reading user input, and validating LED on/off responses via a switch, debugger, and real-time port.

Understand how analog signals from transducers convert to digital numbers with ADCs, enabling microcontrollers to read sensors, and how 8–24 bit resolutions and Vref affect step size.

Explore adc independent modes on stm32l4 by comparing single channel single conversion, multi-channel single conversion, single channel continuous conversion, multi-channel continuous conversion, and injected continuous conversion.

Develop an adc driver by configuring clock access to the adc modules and GPA pins as adc inputs, select channel nine, calibrate, enable the regulator, and read data after conversion.

Develop an stm32l4 adc driver init by enabling clocks and configuring analog mode, and connecting the analog switch. Calibrate, enable, start conversion, and read end-of-conversion flag from the data register.

Develop the adc single conversion driver by configuring the adc to single conversion mode and observing that the conversion runs once and then stops.

Understand the Cortex system tick timer, a 24-bit down counter that drives the real-time heartbeat, with current value, reload value, and system control registers managing clock source and interrupts.

Learn to implement a precise system tick timer driver on a Cortex-M4, configuring systick for millisecond delays using reload and count flags, with internal or external clock sources.

Develop a general purpose timer driver by selecting a timer, configuring the APB clock, and setting prescaler and auto-reload values to achieve one hertz and enable the timer.

Develop a timer output compare driver by configuring timer 2 channel 1 in output compare mode, enabling APB1 clock and alternate function, and starting the counter for 1 Hz beeps.

Understand how interrupts notify the cpu to service modules via the interrupt service routine. Explore how the nvic, vector table, external interrupt lines, and priority configuration enable ISR execution.

Develop a GPIO interrupt driver for STM32L4 by configuring PC13 as external interrupt, enabling clocks, setting GPIO mode, unmasking the interrupt, and selecting a falling-edge trigger.

Test the STM32L4 bare-metal GPIO interrupt driver by configuring input and output, handling the interrupt in the handler, clearing the pending register, and printing status with printf.

Develop a systick interrupt driver for stm32l4 bare-metal. Enable the systick, configure a 1 hz timer from a 4 mhz clock, and implement the interrupt callback that prints a message.

Develop a timer interrupt driver for a general-purpose timer by enabling the timer, configuring auto-reload values, enabling update interrupts, and wiring a time1 interrupt to a callback.

Master the I2C two-wire protocol, with SCL and SDA lines and pull-up resistors; learn start/stop conditions, address and data frames, MSB first, and clock speeds from 100 kHz to 3.4 MHz.

Implement the I2C slave configuration in a STM32L4 bare-metal project by enabling clocks, mapping pins to I2C, enabling pull-ups, setting the device address, and enabling interrupts.

Implement the i2c master configuration function by enabling gpio and i2c clocks, configuring pc0 and pc1 as alternate function open-drain with pull-ups, and setting i2c timing for master operation.

Implement the I2C master communication sequence by configuring slave and master, setting seven-bit addressing, transfer size, transmitting data via TXDR with TXI, and clearing stop flags with the ICR.

Implement an I2C slave interrupt handler on STM32L4, validate the address, enable IREX, read data from the I2C receive data register, and trigger a completion callback.

Explore the serial peripheral interface (spi) basics, including master-slave configurations, clock polarity and phase, mosi/miso data lines, ss selection, and full-duplex data transfer.

Configure the SPI peripheral by enabling its clock, selecting the SPI unit, and setting polarity, phase, duplex mode, 8-bit data, master mode, and slave management before enabling transmit and receive.

Implement SPI master configuration function by setting SPI1 as master and SPI3 as slave, enabling clocks, configuring pins for alternate functions, establishing clock polarity and phase, speed, and interrupts.

Configure and test an SPI rx/tx driver between master and slave, implementing interrupt-driven callbacks, data buffers, and cross-device wiring to verify communication.