Initial Release
This commit is contained in:
1
src/rp2_common/hardware_uart/CMakeLists.txt
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1
src/rp2_common/hardware_uart/CMakeLists.txt
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pico_simple_hardware_target(uart)
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432
src/rp2_common/hardware_uart/include/hardware/uart.h
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432
src/rp2_common/hardware_uart/include/hardware/uart.h
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/*
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* Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
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*
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* SPDX-License-Identifier: BSD-3-Clause
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*/
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#ifndef _HARDWARE_UART_H
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#define _HARDWARE_UART_H
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#include "pico.h"
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#include "hardware/structs/uart.h"
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// PICO_CONFIG: PARAM_ASSERTIONS_ENABLED_UART, Enable/disable assertions in the UART module, type=bool, default=0, group=hardware_uart
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#ifndef PARAM_ASSERTIONS_ENABLED_UART
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#define PARAM_ASSERTIONS_ENABLED_UART 0
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#endif
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#ifdef __cplusplus
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extern "C" {
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#endif
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// PICO_CONFIG: PICO_UART_ENABLE_CRLF_SUPPORT, Enable/disable CR/LF translation support, type=bool, default=1, group=hardware_uart
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#ifndef PICO_UART_ENABLE_CRLF_SUPPORT
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#define PICO_UART_ENABLE_CRLF_SUPPORT 1
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#endif
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// PICO_CONFIG: PICO_UART_DEFAULT_CRLF, Enable/disable CR/LF translation on UART, type=bool, default=0, depends=PICO_UART_ENABLE_CRLF_SUPPORT, group=hardware_uart
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#ifndef PICO_UART_DEFAULT_CRLF
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#define PICO_UART_DEFAULT_CRLF 0
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#endif
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// PICO_CONFIG: PICO_DEFAULT_UART, Define the default UART used for printf etc, default=0, group=hardware_uart
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#ifndef PICO_DEFAULT_UART
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#define PICO_DEFAULT_UART 0 ///< Default UART instance
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#endif
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// PICO_CONFIG: PICO_DEFAULT_UART_BAUD_RATE, Define the default UART baudrate, max=921600, default=115200, group=hardware_uart
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#ifndef PICO_DEFAULT_UART_BAUD_RATE
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#define PICO_DEFAULT_UART_BAUD_RATE 115200 ///< Default baud rate
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#endif
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// PICO_CONFIG: PICO_DEFAULT_UART_TX_PIN, Define the default UART TX pin, min=0, max=29, default=0, group=hardware_uart
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#ifndef PICO_DEFAULT_UART_TX_PIN
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#define PICO_DEFAULT_UART_TX_PIN 0 ///< Default TX pin
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#endif
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// PICO_CONFIG: PICO_DEFAULT_UART_RX_PIN, Define the default UART RX pin, min=0, max=29, default=1, group=hardware_uart
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#ifndef PICO_DEFAULT_UART_RX_PIN
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#define PICO_DEFAULT_UART_RX_PIN 1 ///< Default RX pin
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#endif
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/** \file hardware/uart.h
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* \defgroup hardware_uart hardware_uart
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*
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* Hardware UART API
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*
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* RP2040 has 2 identical instances of a UART peripheral, based on the ARM PL011. Each UART can be connected to a number
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* of GPIO pins as defined in the GPIO muxing.
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*
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* Only the TX, RX, RTS, and CTS signals are
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* connected, meaning that the modem mode and IrDA mode of the PL011 are not supported.
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*
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* \subsection uart_example Example
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* \addtogroup hardware_uart
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*
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* \code
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* int main() {
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*
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* // Initialise UART 0
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* uart_init(uart0, 115200);
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*
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* // Set the GPIO pin mux to the UART - 0 is TX, 1 is RX
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* gpio_set_function(0, GPIO_FUNC_UART);
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* gpio_set_function(1, GPIO_FUNC_UART);
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*
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* uart_puts(uart0, "Hello world!");
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* }
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* \endcode
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*/
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// Currently always a pointer to hw but it might not be in the future
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typedef struct uart_inst uart_inst_t;
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/** The UART identifiers for use in UART functions.
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*
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* e.g. uart_init(uart1, 48000)
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*
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* \ingroup hardware_uart
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* @{
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*/
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#define uart0 ((uart_inst_t * const)uart0_hw) ///< Identifier for UART instance 0
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#define uart1 ((uart_inst_t * const)uart1_hw) ///< Identifier for UART instance 1
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/** @} */
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#ifndef PICO_DEFAULT_UART_INSTANCE
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#define PICO_DEFAULT_UART_INSTANCE (__CONCAT(uart,PICO_DEFAULT_UART))
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#endif
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#define uart_default PICO_DEFAULT_UART_INSTANCE
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/*! \brief Convert UART instance to hardware instance number
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* \ingroup hardware_uart
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*
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* \param uart UART instance
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* \return Number of UART, 0 or 1.
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*/
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static inline uint uart_get_index(uart_inst_t *uart) {
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invalid_params_if(UART, uart != uart0 && uart != uart1);
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return uart == uart1 ? 1 : 0;
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}
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static inline uart_hw_t *uart_get_hw(uart_inst_t *uart) {
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uart_get_index(uart); // check it is a hw uart
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return (uart_hw_t *)uart;
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}
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/** \brief UART Parity enumeration
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* \ingroup hardware_uart
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*/
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typedef enum {
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UART_PARITY_NONE,
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UART_PARITY_EVEN,
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UART_PARITY_ODD
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} uart_parity_t;
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// ----------------------------------------------------------------------------
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// Setup
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/*! \brief Initialise a UART
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* \ingroup hardware_uart
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*
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* Put the UART into a known state, and enable it. Must be called before other
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* functions.
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*
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* \note There is no guarantee that the baudrate requested will be possible, the nearest will be chosen,
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* and this function will return the configured baud rate.
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*
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* \param uart UART instance. \ref uart0 or \ref uart1
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* \param baudrate Baudrate of UART in Hz
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* \return Actual set baudrate
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*/
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uint uart_init(uart_inst_t *uart, uint baudrate);
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/*! \brief DeInitialise a UART
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* \ingroup hardware_uart
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*
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* Disable the UART if it is no longer used. Must be reinitialised before
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* being used again.
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*
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* \param uart UART instance. \ref uart0 or \ref uart1
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*/
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void uart_deinit(uart_inst_t *uart);
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/*! \brief Set UART baud rate
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* \ingroup hardware_uart
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*
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* Set baud rate as close as possible to requested, and return actual rate selected.
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*
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* \param uart UART instance. \ref uart0 or \ref uart1
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* \param baudrate Baudrate in Hz
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*/
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uint uart_set_baudrate(uart_inst_t *uart, uint baudrate);
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/*! \brief Set UART flow control CTS/RTS
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* \ingroup hardware_uart
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*
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* \param uart UART instance. \ref uart0 or \ref uart1
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* \param cts If true enable flow control of TX by clear-to-send input
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* \param rts If true enable assertion of request-to-send output by RX flow control
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*/
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static inline void uart_set_hw_flow(uart_inst_t *uart, bool cts, bool rts) {
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hw_write_masked(&uart_get_hw(uart)->cr,
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(!!cts << UART_UARTCR_CTSEN_LSB) | (!!rts << UART_UARTCR_RTSEN_LSB),
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UART_UARTCR_RTSEN_BITS | UART_UARTCR_CTSEN_BITS);
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}
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/*! \brief Set UART data format
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* \ingroup hardware_uart
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*
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* Configure the data format (bits etc() for the UART
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*
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* \param uart UART instance. \ref uart0 or \ref uart1
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* \param data_bits Number of bits of data. 5..8
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* \param stop_bits Number of stop bits 1..2
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* \param parity Parity option.
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*/
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static inline void uart_set_format(uart_inst_t *uart, uint data_bits, uint stop_bits, uart_parity_t parity) {
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invalid_params_if(UART, data_bits < 5 || data_bits > 8);
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invalid_params_if(UART, stop_bits != 1 && stop_bits != 2);
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invalid_params_if(UART, parity != UART_PARITY_NONE && parity != UART_PARITY_EVEN && parity != UART_PARITY_ODD);
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hw_write_masked(&uart_get_hw(uart)->lcr_h,
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((data_bits - 5) << UART_UARTLCR_H_WLEN_LSB) |
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((stop_bits - 1) << UART_UARTLCR_H_STP2_LSB) |
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((parity != UART_PARITY_NONE) << UART_UARTLCR_H_PEN_LSB) |
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((parity == UART_PARITY_EVEN) << UART_UARTLCR_H_EPS_LSB),
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UART_UARTLCR_H_WLEN_BITS |
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UART_UARTLCR_H_STP2_BITS |
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UART_UARTLCR_H_PEN_BITS |
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UART_UARTLCR_H_EPS_BITS);
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}
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/*! \brief Setup UART interrupts
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* \ingroup hardware_uart
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*
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* Enable the UART's interrupt output. An interrupt handler will need to be installed prior to calling
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* this function.
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*
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* \param uart UART instance. \ref uart0 or \ref uart1
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* \param rx_has_data If true an interrupt will be fired when the RX FIFO contain data.
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* \param tx_needs_data If true an interrupt will be fired when the TX FIFO needs data.
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*/
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static inline void uart_set_irq_enables(uart_inst_t *uart, bool rx_has_data, bool tx_needs_data) {
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uart_get_hw(uart)->imsc = (!!tx_needs_data << UART_UARTIMSC_TXIM_LSB) |
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(!!rx_has_data << UART_UARTIMSC_RXIM_LSB);
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if (rx_has_data) {
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// Set minimum threshold
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hw_write_masked(&uart_get_hw(uart)->ifls, 0 << UART_UARTIFLS_RXIFLSEL_LSB,
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UART_UARTIFLS_RXIFLSEL_BITS);
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}
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if (tx_needs_data) {
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// Set maximum threshold
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hw_write_masked(&uart_get_hw(uart)->ifls, 0 << UART_UARTIFLS_TXIFLSEL_LSB,
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UART_UARTIFLS_TXIFLSEL_BITS);
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}
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}
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/*! \brief Test if specific UART is enabled
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* \ingroup hardware_uart
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*
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* \param uart UART instance. \ref uart0 or \ref uart1
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* \return true if the UART is enabled
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*/
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static inline bool uart_is_enabled(uart_inst_t *uart) {
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return !!(uart_get_hw(uart)->cr & UART_UARTCR_UARTEN_BITS);
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}
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/*! \brief Enable/Disable the FIFOs on specified UART
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* \ingroup hardware_uart
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*
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* \param uart UART instance. \ref uart0 or \ref uart1
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* \param enabled true to enable FIFO (default), false to disable
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*/
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static inline void uart_set_fifo_enabled(uart_inst_t *uart, bool enabled) {
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hw_write_masked(&uart_get_hw(uart)->lcr_h,
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(!!enabled << UART_UARTLCR_H_FEN_LSB),
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UART_UARTLCR_H_FEN_BITS);
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}
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// ----------------------------------------------------------------------------
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// Generic input/output
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/*! \brief Determine if space is available in the TX FIFO
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* \ingroup hardware_uart
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*
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* \param uart UART instance. \ref uart0 or \ref uart1
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* \return false if no space available, true otherwise
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*/
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static inline bool uart_is_writable(uart_inst_t *uart) {
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return !(uart_get_hw(uart)->fr & UART_UARTFR_TXFF_BITS);
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}
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/*! \brief Wait for the UART TX fifo to be drained
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* \ingroup hardware_uart
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*
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* \param uart UART instance. \ref uart0 or \ref uart1
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*/
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static inline void uart_tx_wait_blocking(uart_inst_t *uart) {
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while (uart_get_hw(uart)->fr & UART_UARTFR_BUSY_BITS) tight_loop_contents();
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}
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/*! \brief Determine whether data is waiting in the RX FIFO
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* \ingroup hardware_uart
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*
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* \param uart UART instance. \ref uart0 or \ref uart1
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* \return 0 if no data available, otherwise the number of bytes, at least, that can be read
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*
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* \note HW limitations mean this function will return either 0 or 1.
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*/
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static inline bool uart_is_readable(uart_inst_t *uart) {
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// PL011 doesn't expose levels directly, so return values are only 0 or 1
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return !(uart_get_hw(uart)->fr & UART_UARTFR_RXFE_BITS);
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}
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/*! \brief Write to the UART for transmission.
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* \ingroup hardware_uart
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*
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* This function will block until all the data has been sent to the UART
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*
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* \param uart UART instance. \ref uart0 or \ref uart1
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* \param src The bytes to send
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* \param len The number of bytes to send
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*/
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static inline void uart_write_blocking(uart_inst_t *uart, const uint8_t *src, size_t len) {
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for (size_t i = 0; i < len; ++i) {
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while (!uart_is_writable(uart))
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tight_loop_contents();
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uart_get_hw(uart)->dr = *src++;
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}
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}
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/*! \brief Read from the UART
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* \ingroup hardware_uart
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*
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* This function will block until all the data has been received from the UART
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*
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* \param uart UART instance. \ref uart0 or \ref uart1
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* \param dst Buffer to accept received bytes
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* \param len The number of bytes to receive.
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*/
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static inline void uart_read_blocking(uart_inst_t *uart, uint8_t *dst, size_t len) {
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for (size_t i = 0; i < len; ++i) {
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while (!uart_is_readable(uart))
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tight_loop_contents();
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*dst++ = uart_get_hw(uart)->dr;
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}
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||||
}
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||||
// ----------------------------------------------------------------------------
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// UART-specific operations and aliases
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||||
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/*! \brief Write single character to UART for transmission.
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* \ingroup hardware_uart
|
||||
*
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* This function will block until all the character has been sent
|
||||
*
|
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* \param uart UART instance. \ref uart0 or \ref uart1
|
||||
* \param c The character to send
|
||||
*/
|
||||
static inline void uart_putc_raw(uart_inst_t *uart, char c) {
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uart_write_blocking(uart, (const uint8_t *) &c, 1);
|
||||
}
|
||||
|
||||
/*! \brief Write single character to UART for transmission, with optional CR/LF conversions
|
||||
* \ingroup hardware_uart
|
||||
*
|
||||
* This function will block until the character has been sent
|
||||
*
|
||||
* \param uart UART instance. \ref uart0 or \ref uart1
|
||||
* \param c The character to send
|
||||
*/
|
||||
static inline void uart_putc(uart_inst_t *uart, char c) {
|
||||
#if PICO_UART_ENABLE_CRLF_SUPPORT
|
||||
extern short uart_char_to_line_feed[NUM_UARTS];
|
||||
if (uart_char_to_line_feed[uart_get_index(uart)] == c)
|
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uart_putc_raw(uart, '\r');
|
||||
#endif
|
||||
uart_putc_raw(uart, c);
|
||||
}
|
||||
|
||||
/*! \brief Write string to UART for transmission, doing any CR/LF conversions
|
||||
* \ingroup hardware_uart
|
||||
*
|
||||
* This function will block until the entire string has been sent
|
||||
*
|
||||
* \param uart UART instance. \ref uart0 or \ref uart1
|
||||
* \param s The null terminated string to send
|
||||
*/
|
||||
static inline void uart_puts(uart_inst_t *uart, const char *s) {
|
||||
#if PICO_UART_ENABLE_CRLF_SUPPORT
|
||||
bool last_was_cr = false;
|
||||
while (*s) {
|
||||
// Don't add extra carriage returns if one is present
|
||||
if (last_was_cr)
|
||||
uart_putc_raw(uart, *s);
|
||||
else
|
||||
uart_putc(uart, *s);
|
||||
last_was_cr = *s++ == '\r';
|
||||
}
|
||||
#else
|
||||
while (*s)
|
||||
uart_putc(uart, *s++);
|
||||
#endif
|
||||
}
|
||||
|
||||
/*! \brief Read a single character to UART
|
||||
* \ingroup hardware_uart
|
||||
*
|
||||
* This function will block until the character has been read
|
||||
*
|
||||
* \param uart UART instance. \ref uart0 or \ref uart1
|
||||
* \return The character read.
|
||||
*/
|
||||
static inline char uart_getc(uart_inst_t *uart) {
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||||
char c;
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||||
uart_read_blocking(uart, (uint8_t *) &c, 1);
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||||
return c;
|
||||
}
|
||||
|
||||
/*! \brief Assert a break condition on the UART transmission.
|
||||
* \ingroup hardware_uart
|
||||
*
|
||||
* \param uart UART instance. \ref uart0 or \ref uart1
|
||||
* \param en Assert break condition (TX held low) if true. Clear break condition if false.
|
||||
*/
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||||
static inline void uart_set_break(uart_inst_t *uart, bool en) {
|
||||
if (en)
|
||||
hw_set_bits(&uart_get_hw(uart)->lcr_h, UART_UARTLCR_H_BRK_BITS);
|
||||
else
|
||||
hw_clear_bits(&uart_get_hw(uart)->lcr_h, UART_UARTLCR_H_BRK_BITS);
|
||||
}
|
||||
|
||||
/*! \brief Set CR/LF conversion on UART
|
||||
* \ingroup hardware_uart
|
||||
*
|
||||
* \param uart UART instance. \ref uart0 or \ref uart1
|
||||
* \param translate If true, convert line feeds to carriage return on transmissions
|
||||
*/
|
||||
void uart_set_translate_crlf(uart_inst_t *uart, bool translate);
|
||||
|
||||
/*! \brief Wait for the default UART'S TX fifo to be drained
|
||||
* \ingroup hardware_uart
|
||||
*/
|
||||
static inline void uart_default_tx_wait_blocking() {
|
||||
uart_tx_wait_blocking(uart_default);
|
||||
}
|
||||
|
||||
/*! \brief Wait for up to a certain number of microseconds for the RX FIFO to be non empty
|
||||
* \ingroup hardware_uart
|
||||
*
|
||||
* \param uart UART instance. \ref uart0 or \ref uart1
|
||||
* \param us the number of microseconds to wait at most (may be 0 for an instantaneous check)
|
||||
* \return true if the RX FIFO became non empty before the timeout, false otherwise
|
||||
*/
|
||||
bool uart_is_readable_within_us(uart_inst_t *uart, uint32_t us);
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
#endif
|
||||
|
||||
#endif
|
112
src/rp2_common/hardware_uart/uart.c
Normal file
112
src/rp2_common/hardware_uart/uart.c
Normal file
@ -0,0 +1,112 @@
|
||||
/*
|
||||
* Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
|
||||
*
|
||||
* SPDX-License-Identifier: BSD-3-Clause
|
||||
*/
|
||||
|
||||
#include "hardware/address_mapped.h"
|
||||
#include "hardware/platform_defs.h"
|
||||
#include "hardware/uart.h"
|
||||
|
||||
#include "hardware/structs/uart.h"
|
||||
#include "hardware/resets.h"
|
||||
#include "hardware/clocks.h"
|
||||
#include "hardware/timer.h"
|
||||
|
||||
#include "pico/assert.h"
|
||||
#include "pico.h"
|
||||
|
||||
check_hw_layout(uart_hw_t, fr, UART_UARTFR_OFFSET);
|
||||
check_hw_layout(uart_hw_t, dmacr, UART_UARTDMACR_OFFSET);
|
||||
|
||||
#if PICO_UART_ENABLE_CRLF_SUPPORT
|
||||
short uart_char_to_line_feed[NUM_UARTS];
|
||||
#endif
|
||||
|
||||
/// \tag::uart_reset[]
|
||||
static inline void uart_reset(uart_inst_t *uart) {
|
||||
invalid_params_if(UART, uart != uart0 && uart != uart1);
|
||||
reset_block(uart_get_index(uart) ? RESETS_RESET_UART1_BITS : RESETS_RESET_UART0_BITS);
|
||||
}
|
||||
|
||||
static inline void uart_unreset(uart_inst_t *uart) {
|
||||
invalid_params_if(UART, uart != uart0 && uart != uart1);
|
||||
unreset_block_wait(uart_get_index(uart) ? RESETS_RESET_UART1_BITS : RESETS_RESET_UART0_BITS);
|
||||
}
|
||||
/// \end::uart_reset[]
|
||||
|
||||
/// \tag::uart_init[]
|
||||
uint uart_init(uart_inst_t *uart, uint baudrate) {
|
||||
invalid_params_if(UART, uart != uart0 && uart != uart1);
|
||||
|
||||
if (clock_get_hz(clk_peri) == 0)
|
||||
return 0;
|
||||
|
||||
uart_reset(uart);
|
||||
uart_unreset(uart);
|
||||
|
||||
#if PICO_UART_ENABLE_CRLF_SUPPORT
|
||||
uart_set_translate_crlf(uart, PICO_UART_DEFAULT_CRLF);
|
||||
#endif
|
||||
|
||||
// Any LCR writes need to take place before enabling the UART
|
||||
uint baud = uart_set_baudrate(uart, baudrate);
|
||||
uart_set_format(uart, 8, 1, UART_PARITY_NONE);
|
||||
|
||||
// Enable the UART, both TX and RX
|
||||
uart_get_hw(uart)->cr = UART_UARTCR_UARTEN_BITS | UART_UARTCR_TXE_BITS | UART_UARTCR_RXE_BITS;
|
||||
// Enable FIFOs
|
||||
hw_set_bits(&uart_get_hw(uart)->lcr_h, UART_UARTLCR_H_FEN_BITS);
|
||||
// Always enable DREQ signals -- no harm in this if DMA is not listening
|
||||
uart_get_hw(uart)->dmacr = UART_UARTDMACR_TXDMAE_BITS | UART_UARTDMACR_RXDMAE_BITS;
|
||||
|
||||
return baud;
|
||||
}
|
||||
/// \end::uart_init[]
|
||||
|
||||
void uart_deinit(uart_inst_t *uart) {
|
||||
invalid_params_if(UART, uart != uart0 && uart != uart1);
|
||||
uart_reset(uart);
|
||||
}
|
||||
|
||||
/// \tag::uart_set_baudrate[]
|
||||
uint uart_set_baudrate(uart_inst_t *uart, uint baudrate) {
|
||||
invalid_params_if(UART, baudrate == 0);
|
||||
uint32_t baud_rate_div = (8 * clock_get_hz(clk_peri) / baudrate);
|
||||
uint32_t baud_ibrd = baud_rate_div >> 7;
|
||||
uint32_t baud_fbrd = ((baud_rate_div & 0x7f) + 1) / 2;
|
||||
invalid_params_if(UART, (baud_ibrd > 65535) || (baud_ibrd == 0));
|
||||
|
||||
// Load PL011's baud divisor registers
|
||||
uart_get_hw(uart)->ibrd = baud_ibrd;
|
||||
if (baud_ibrd == 65535) {
|
||||
uart_get_hw(uart)->fbrd = 0;
|
||||
} else {
|
||||
uart_get_hw(uart)->fbrd = baud_fbrd;
|
||||
}
|
||||
|
||||
// PL011 needs a (dummy) line control register write to latch in the
|
||||
// divisors. We don't want to actually change LCR contents here.
|
||||
hw_set_bits(&uart_get_hw(uart)->lcr_h, 0);
|
||||
|
||||
// See datasheet
|
||||
uint baud = (4 * clock_get_hz(clk_peri)) / (64 * baud_ibrd + baud_fbrd);
|
||||
return baud;
|
||||
}
|
||||
/// \end::uart_set_baudrate[]
|
||||
|
||||
void uart_set_translate_crlf(uart_inst_t *uart, bool crlf) {
|
||||
#if PICO_UART_ENABLE_CRLF_SUPPORT
|
||||
uart_char_to_line_feed[uart_get_index(uart)] = crlf ? '\n' : 0x100;
|
||||
#else
|
||||
panic_unsupported();
|
||||
#endif
|
||||
}
|
||||
|
||||
bool uart_is_readable_within_us(uart_inst_t *uart, uint32_t us) {
|
||||
uint32_t t = time_us_32();
|
||||
do {
|
||||
if (uart_is_readable(uart)) return true;
|
||||
} while ((time_us_32() - t) <= us);
|
||||
return false;
|
||||
}
|
Reference in New Issue
Block a user