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Diffstat (limited to 'libmaple/stm32f1/usart.c')
| -rw-r--r-- | libmaple/stm32f1/usart.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/libmaple/stm32f1/usart.c b/libmaple/stm32f1/usart.c new file mode 100644 index 0000000..b3b849f --- /dev/null +++ b/libmaple/stm32f1/usart.c @@ -0,0 +1,170 @@ +/****************************************************************************** + * The MIT License + * + * Copyright (c) 2012 LeafLabs, LLC. + * Copyright (c) 2010 Perry Hung. + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + *****************************************************************************/ + +/** + * @file libmaple/stm32f1/usart.c + * @author Marti Bolivar <mbolivar@leaflabs.com>, + * Perry Hung <perry@leaflabs.com> + * @brief STM32F1 USART. + */ + +#include <libmaple/usart.h> +#include <libmaple/gpio.h> +#include "usart_private.h" + +/* + * Devices + */ + +static ring_buffer usart1_rb; +static usart_dev usart1 = { + .regs = USART1_BASE, + .rb = &usart1_rb, + .max_baud = 4500000UL, + .clk_id = RCC_USART1, + .irq_num = NVIC_USART1, +}; +/** USART1 device */ +usart_dev *USART1 = &usart1; + +static ring_buffer usart2_rb; +static usart_dev usart2 = { + .regs = USART2_BASE, + .rb = &usart2_rb, + .max_baud = 2250000UL, + .clk_id = RCC_USART2, + .irq_num = NVIC_USART2, +}; +/** USART2 device */ +usart_dev *USART2 = &usart2; + +static ring_buffer usart3_rb; +static usart_dev usart3 = { + .regs = USART3_BASE, + .rb = &usart3_rb, + .max_baud = 2250000UL, + .clk_id = RCC_USART3, + .irq_num = NVIC_USART3, +}; +/** USART3 device */ +usart_dev *USART3 = &usart3; + +#if defined(STM32_HIGH_DENSITY) || defined(STM32_XL_DENSITY) +static ring_buffer uart4_rb; +static usart_dev uart4 = { + .regs = UART4_BASE, + .rb = &uart4_rb, + .max_baud = 2250000UL, + .clk_id = RCC_UART4, + .irq_num = NVIC_UART4, +}; +/** UART4 device */ +usart_dev *UART4 = &uart4; + +static ring_buffer uart5_rb; +static usart_dev uart5 = { + .regs = UART5_BASE, + .rb = &uart5_rb, + .max_baud = 2250000UL, + .clk_id = RCC_UART5, + .irq_num = NVIC_UART5, +}; +/** UART5 device */ +usart_dev *UART5 = &uart5; +#endif + +/* + * Routines + */ + +void usart_config_gpios_async(usart_dev *udev, + gpio_dev *rx_dev, uint8 rx, + gpio_dev *tx_dev, uint8 tx, + unsigned flags) { + gpio_set_mode(rx_dev, rx, GPIO_INPUT_FLOATING); + gpio_set_mode(tx_dev, tx, GPIO_AF_OUTPUT_PP); +} + +void usart_set_baud_rate(usart_dev *dev, uint32 clock_speed, uint32 baud) { + uint32 integer_part; + uint32 fractional_part; + uint32 tmp; + + /* Figure out the clock speed, if the user doesn't give one. */ + if (clock_speed == 0) { + clock_speed = _usart_clock_freq(dev); + } + ASSERT(clock_speed); + + /* Convert desired baud rate to baud rate register setting. */ + integer_part = (25 * clock_speed) / (4 * baud); + tmp = (integer_part / 100) << 4; + fractional_part = integer_part - (100 * (tmp >> 4)); + tmp |= (((fractional_part * 16) + 50) / 100) & ((uint8)0x0F); + + dev->regs->BRR = (uint16)tmp; +} + +/** + * @brief Call a function on each USART. + * @param fn Function to call. + */ +void usart_foreach(void (*fn)(usart_dev*)) { + fn(USART1); + fn(USART2); + fn(USART3); +#ifdef STM32_HIGH_DENSITY + fn(UART4); + fn(UART5); +#endif +} + +/* + * Interrupt handlers. + */ + +void __irq_usart1(void) { + usart_irq(&usart1_rb, USART1_BASE); +} + +void __irq_usart2(void) { + usart_irq(&usart2_rb, USART2_BASE); +} + +void __irq_usart3(void) { + usart_irq(&usart3_rb, USART3_BASE); +} + +#ifdef STM32_HIGH_DENSITY +void __irq_uart4(void) { + usart_irq(&uart4_rb, UART4_BASE); +} + +void __irq_uart5(void) { + usart_irq(&uart5_rb, UART5_BASE); +} +#endif |