.. _informational_requirements: Informational requirements ========================== .. req:: label :id: REQ_INT3_1732783938 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: USART is used for serial communication between two devices. .. req:: label :id: REQ_INT3_1732785337 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: The functionality of the USART includes mode of operation such as data transmission and reception .. req:: label :id: REQ_INT3_1732785381 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: The functionality of the USART includes mode of operation such as controlling transmission speed. .. req:: label :id: REQ_INT3_1732785452 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: The functionality of the USART includes mode of operation such as operating modes(synchronous and asynchronous). .. req:: label :id: REQ_INT3_1732785522 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: The functionality of the USART includes modes of operation such as additional flow control and error detection failures. .. req:: label :id: REQ_INT3_1732785580 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: Transmitter is sending data .. req:: label :id: REQ_INT3_1732785686 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: Receiever is recieving data .. req:: label :id: REQ_INT3_1732785721 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: Control register are used to configure parameters such as baud rate, operating mode and parity. .. req:: label :id: REQ_INT3_1732785783 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: USART is used to support asynchronous and synchronous operation modes .. req:: label :id: REQ_INT3_1732785864 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: USART has configurable baud rate for flexible communication speed .. req:: label :id: REQ_INT3_1732786316 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: Baud rate is the measure of the number of changes to the signal (per second) that propagate through a transmission medium. .. req:: label :id: REQ_INT3_1732785935 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: USART has configurable data size(8-bit, 9-bit). .. req:: label :id: REQ_INT3_1732797208 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: Odd parity means that the total number of 1s in the data should always be odd number, if bit is corrupted during transmission, the parity check will fail. .. req:: label :id: REQ_INT3_1732797345 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: Even parity means that the total number of 1s must always be an even number, if the data is recieved and the total number of 1s is not even, this indicates an error during transmission. .. req:: label :id: REQ_INT3_1732794782 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: USART provides even parity control for error detection .. req:: label :id: REQ_INT3_1732786086 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: USART provides support for Direct Memory Access, speeding up data transmission. .. req:: label :id: REQ_INT3_1732786173 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: Single-wire Half-duplex uses one pin for both data transmission and reception .. req:: label :id: REQ_INT3_1732786486 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: STM32F411 supports USART1 which is connected to APB2 bus and uses pins PA9 (TX) and PA10 (RX) .. req:: label :id: REQ_INT3_1732786595 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: STM32F411 supports USART2 connected to the APB1 bus and uses pins PA2 (TX) and PA3 (RX). .. req:: label :id: REQ_INT3_1732786700 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: STM32F411 supports USART6 connected to APB2 bus and uses pins PC6 (TX) and PC7 (RX). .. req:: label :id: REQ_INT3_1732786813 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: USART has two modes: asynchronous mode and synchronous mode .. req:: label :id: REQ_INT3_1732787036 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: In asynchronous mode start and stop bits are used to mark the beginning and end of a data packet .. req:: label :id: REQ_INT3_1732787558 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: Formula for Baud Rate = fPLCK / (8*(2 - OVER8) * USARTDIV) where FPLCK=Clock frequency, OVER8=Oversampling configuration, USARTDIV=Value in the BRR register. .. req:: label :id: REQ_INT3_1732787756 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: In USART the baud rate is controlled using the Baud Rate Register. .. req:: label :id: REQ_INT3_1732787805 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: The baud rate depends on the peripheral clock frequency (fPCLK) and the configuration of the USART peripheral. .. req:: label :id: REQ_INT3_1732787864 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: The oversampling factor (OVER8) can be adjusted to control the precision and speed of data transmission. .. req:: label :id: REQ_INT3_1732787935 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: 16x oversampling provides more stable signal .. req:: label :id: REQ_INT3_1732787989 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: 8x oversampling provides faster data transmission, but with potential loss in accuracy. .. req:: label :id: REQ_INT3_1732788084 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: The CR1 is a critical regiter used to configure Baud Rate, Data bits, Stop bits, Parity, Mode of communication for USART communication. .. req:: label :id: REQ_INT3_1732795059 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: Basic parameters for USART communication are: Baud Rate, Word lenght, Stop bits, Parity, Flow Control, Oversampling .. req:: label :id: REQ_INT3_1732788145 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: UE (Usart Enable) bit enables or disables the USART peripheral .. req:: label :id: REQ_INT3_1732788245 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: TE (Transmitter Enable) bit enables or disables data transmission through the USART .. req:: label :id: REQ_INT3_1732788324 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: RE (Reciever Enable) bit enables or disables data reception through the USART .. req:: label :id: REQ_INT3_1732788446 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: Oversampling refers to taking multiple samples of the data during a single bit cycle to improve the accuracy in data reception. .. req:: label :id: REQ_INT3_1732796410 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: USART1 uses AF1, AF4 and AF7 .. req:: label :id: REQ_INT3_1732796534 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: USART2 uses AF1, AF4 and AF7 .. req:: label :id: REQ_INT3_1732796573 :status: Draft :date-released: :priority: Low :submitted-by: Semin Murtic :modified-by: :category: Informational :safety-asil: :references: :verification-and-validation: USART6 uses AF5, AF8 and AF11