The **STM32L412R8T3PTR** is a member of the STM32L4 series, designed by STMicroelectronics. It is an ultra-low-power microcontroller based on the high-performance Arm® Cortex®-M4 32-bit RISC core. --- ### 1. Key Technical Specifications | Feature | Specification | | :--- | :--- | | **Core** | Arm® 32-bit Cortex®-M4 CPU with FPU | | **Max Frequency** | 80 MHz | | **Flash Memory** | 64 KB | | **SRAM** | 40 KB | | **Operating Voltage** | 1.71 V to 3.6 V | | **Package** | LQFP64 (10x10 mm) | | **Operating Temp** | -40°C to 105°C | --- ### 2. Core Functional Blocks #### Power Management This chip is optimized for battery-operated devices. It features multiple low-power modes: * **Shutdown Mode:** Only 22 nA consumption. * **Standby Mode:** 106 nA (with RTC). * **Stop 2 Mode:** 28 µA/MHz in run mode. * **VBAT Support:** Allows the RTC and backup registers to stay powered even when the main VDD is off. #### Peripheral Connectivity The STM32L412R8T3PTR includes a robust set of communication interfaces: * **I2C:** 3x interfaces (supporting SMBus/PMBus). * **USART/UART:** 3x interfaces (ISO 7816, LIN, IrDA, Modbus). * **SPI:** 2x interfaces. * **USB:** USB 2.0 full-speed crystal-less solution. #### Analog Features * **ADC:** 1x 12-bit ADC (up to 5 Msps) for high-speed sensor data acquisition. * **Internal Voltage Reference:** Provides a stable voltage for analog blocks. * **Comparators:** 2x ultra-low-power comparators. --- ### 3. Pinout and Packaging (LQFP64) The **"R8T3"** suffix indicates specific physical and thermal characteristics: * **R:** 64-pin count. * **8:** 64 KB Flash density. * **T:** LQFP Package type. * **3:** Extended temperature range (-40°C to 105°C). * **PTR:** Packaging suffix (usually indicates "Tape and Reel"). --- ### 4. Sample Code: GPIO Initialization Below is a basic example of how to initialize a GPIO pin (e.g., PA5 for an LED) using the HAL library: ```c void MX_GPIO_Init(void) { GPIO_InitTypeDef GPIO_InitStruct = {0}; /* GPIO Ports Clock Enable */ __HAL_RCC_GPIOA_CLK_ENABLE(); /*Configure GPIO pin Output Level */ HAL_GPIO_WritePin(GPIOA, GPIO_PIN_5, GPIO_PIN_RESET); /*Configure GPIO pin : PA5 */ GPIO_InitStruct.Pin = GPIO_PIN_5; GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP; GPIO_InitStruct.Pull = GPIO_NOPULL; GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW; HAL_GPIO_Init(GPIOA, &GPIO_InitStruct); } ``` ---