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libopencm3-examples/examples/stm32/f3/stm32f3-discovery/spi/spi.c

235 lines
6.3 KiB
C

/*
* This file is part of the libopencm3 project.
*
* Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
* Copyright (C) 2011 Stephen Caudle <scaudle@doceme.com>
* Modified by Fernando Cortes <fermando.corcam@gmail.com>
* modified by Guillermo Rivera <memogrg@gmail.com>
*
* This library is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
#include <libopencm3/stm32/rcc.h>
#include <libopencm3/stm32/usart.h>
#include <libopencm3/stm32/spi.h>
#include <libopencm3/stm32/gpio.h>
#define LBLUE GPIOE, GPIO8
#define LRED GPIOE, GPIO9
#define LORANGE GPIOE, GPIO10
#define LGREEN GPIOE, GPIO11
#define LBLUE2 GPIOE, GPIO12
#define LRED2 GPIOE, GPIO13
#define LORANGE2 GPIOE, GPIO14
#define LGREEN2 GPIOE, GPIO15
#define LD4 GPIOE, GPIO8
#define LD3 GPIOE, GPIO9
#define LD5 GPIOE, GPIO10
#define LD7 GPIOE, GPIO11
#define LD9 GPIOE, GPIO12
#define LD10 GPIOE, GPIO13
#define LD8 GPIOE, GPIO14
#define LD6 GPIOE, GPIO15
static void spi_setup(void)
{
rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_SPI1EN);
/* For spi signal pins */
rcc_peripheral_enable_clock(&RCC_AHBENR, RCC_AHBENR_IOPAEN);
/* For spi mode select on the l3gd20 */
rcc_peripheral_enable_clock(&RCC_AHBENR, RCC_AHBENR_IOPEEN);
/* Setup GPIOE3 pin for spi mode l3gd20 select. */
gpio_mode_setup(GPIOE, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO3);
/* Start with spi communication disabled */
gpio_set(GPIOE, GPIO3);
/* Setup GPIO pins for AF5 for SPI1 signals. */
gpio_mode_setup(GPIOA, GPIO_MODE_AF, GPIO_PUPD_NONE,
GPIO5 | GPIO6 | GPIO7);
gpio_set_af(GPIOA, GPIO_AF5, GPIO5 | GPIO6 | GPIO7);
//spi initialization;
spi_set_master_mode(SPI1);
spi_set_baudrate_prescaler(SPI1, SPI_CR1_BR_FPCLK_DIV_64);
spi_set_clock_polarity_0(SPI1);
spi_set_clock_phase_0(SPI1);
spi_set_full_duplex_mode(SPI1);
spi_set_unidirectional_mode(SPI1); /* bidirectional but in 3-wire */
spi_set_data_size(SPI1, SPI_CR2_DS_8BIT);
spi_enable_software_slave_management(SPI1);
spi_send_msb_first(SPI1);
spi_set_nss_high(SPI1);
//spi_enable_ss_output(SPI1);
spi_fifo_reception_threshold_8bit(SPI1);
SPI_I2SCFGR(SPI1) &= ~SPI_I2SCFGR_I2SMOD;
spi_enable(SPI1);
}
static void usart_setup(void)
{
/* Enable clocks for GPIO port A (for GPIO_USART2_TX) and USART2. */
rcc_peripheral_enable_clock(&RCC_APB1ENR, RCC_APB1ENR_USART2EN);
rcc_peripheral_enable_clock(&RCC_AHBENR, RCC_AHBENR_IOPAEN);
/* Setup GPIO pin GPIO_USART2_TX/GPIO9 on GPIO port A for transmit. */
gpio_mode_setup(GPIOA, GPIO_MODE_AF, GPIO_PUPD_NONE, GPIO2 | GPIO3);
gpio_set_af(GPIOA, GPIO_AF7, GPIO2| GPIO3);
/* Setup UART parameters. */
usart_set_baudrate(USART2, 115200);
usart_set_databits(USART2, 8);
usart_set_stopbits(USART2, USART_STOPBITS_1);
usart_set_mode(USART2, USART_MODE_TX_RX);
usart_set_parity(USART2, USART_PARITY_NONE);
usart_set_flow_control(USART2, USART_FLOWCONTROL_NONE);
/* Finally enable the USART. */
usart_enable(USART2);
}
static void gpio_setup(void)
{
rcc_peripheral_enable_clock(&RCC_AHBENR, RCC_AHBENR_IOPEEN);
gpio_mode_setup(GPIOE, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE,
GPIO8 | GPIO9 | GPIO10 | GPIO11 | GPIO12 | GPIO13 |
GPIO14 | GPIO15);
}
static void my_usart_print_int(uint32_t usart, int32_t value)
{
int8_t i;
int8_t nr_digits = 0;
char buffer[25];
if (value < 0) {
usart_send_blocking(usart, '-');
value = value * -1;
}
if (value == 0) {
usart_send_blocking(usart, '0');
}
while (value > 0) {
buffer[nr_digits++] = "0123456789"[value % 10];
value /= 10;
}
for (i = nr_digits-1; i >= 0; i--) {
usart_send_blocking(usart, buffer[i]);
}
usart_send_blocking(usart, '\r');
usart_send_blocking(usart, '\n');
}
static void clock_setup(void)
{
rcc_clock_setup_hsi(&hsi_8mhz[CLOCK_64MHZ]);
}
#define GYR_RNW (1 << 7) /* Write when zero */
#define GYR_MNS (1 << 6) /* Multiple reads when 1 */
#define GYR_WHO_AM_I 0x0F
#define GYR_OUT_TEMP 0x26
#define GYR_STATUS_REG 0x27
#define GYR_CTRL_REG1 0x20
#define GYR_CTRL_REG1_PD (1 << 3)
#define GYR_CTRL_REG1_XEN (1 << 1)
#define GYR_CTRL_REG1_YEN (1 << 0)
#define GYR_CTRL_REG1_ZEN (1 << 2)
#define GYR_CTRL_REG1_BW_SHIFT 4
#define GYR_CTRL_REG4 0x23
#define GYR_CTRL_REG4_FS_SHIFT 4
#define GYR_OUT_X_L 0x28
#define GYR_OUT_X_H 0x29
int main(void)
{
uint8_t temp;
int16_t gyr_x;
clock_setup();
gpio_setup();
usart_setup();
spi_setup();
gpio_clear(GPIOE, GPIO3);
spi_send8(SPI1, GYR_CTRL_REG1);
spi_read8(SPI1);
spi_send8(SPI1, GYR_CTRL_REG1_PD | GYR_CTRL_REG1_XEN |
GYR_CTRL_REG1_YEN | GYR_CTRL_REG1_ZEN |
(3 << GYR_CTRL_REG1_BW_SHIFT));
spi_read8(SPI1);
gpio_set(GPIOE, GPIO3);
gpio_clear(GPIOE, GPIO3);
spi_send8(SPI1, GYR_CTRL_REG4);
spi_read8(SPI1);
spi_send8(SPI1, (1 << GYR_CTRL_REG4_FS_SHIFT));
spi_read8(SPI1);
gpio_set(GPIOE, GPIO3);
while (1) {
gpio_clear(GPIOE, GPIO3);
spi_send8(SPI1, GYR_WHO_AM_I | GYR_RNW);
spi_read8(SPI1);
spi_send8(SPI1, 0);
temp=spi_read8(SPI1);
my_usart_print_int(USART2, (temp));
gpio_set(GPIOE, GPIO3);
gpio_clear(GPIOE, GPIO3);
spi_send8(SPI1, GYR_STATUS_REG | GYR_RNW);
spi_read8(SPI1);
spi_send8(SPI1, 0);
temp=spi_read8(SPI1);
my_usart_print_int(USART2, (temp));
gpio_set(GPIOE, GPIO3);
gpio_clear(GPIOE, GPIO3);
spi_send8(SPI1, GYR_OUT_TEMP | GYR_RNW);
spi_read8(SPI1);
spi_send8(SPI1, 0);
temp=spi_read8(SPI1);
my_usart_print_int(USART2, (temp));
gpio_set(GPIOE, GPIO3);
gpio_clear(GPIOE, GPIO3);
spi_send8(SPI1, GYR_OUT_X_L | GYR_RNW);
spi_read8(SPI1);
spi_send8(SPI1, 0);
gyr_x=spi_read8(SPI1);
gpio_set(GPIOE, GPIO3);
gpio_clear(GPIOE, GPIO3);
spi_send8(SPI1, GYR_OUT_X_H | GYR_RNW);
spi_read8(SPI1);
spi_send8(SPI1, 0);
gyr_x|=spi_read8(SPI1) << 8;
my_usart_print_int(USART2, (gyr_x));
gpio_set(GPIOE, GPIO3);
int i;
for (i = 0; i < 80000; i++) /* Wait a bit. */
__asm__("nop");
}
return 0;
}