2018-05-28 22:48:44 +03:00

93 lines
3.8 KiB
C

/*
* geany_encoding=koi8-r
* hardware.c - hardware-dependent macros & functions
*
* Copyright 2018 Edward V. Emelianov <eddy@sao.ru, edward.emelianoff@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA.
*
*/
#include "hardware.h"
void gpio_setup(void){
// Set green led (PB3) as output
RCC->AHBENR |= RCC_AHBENR_GPIOBEN | RCC_AHBENR_GPIOAEN;
GPIOB->MODER = GPIO_MODER_MODER3_O;
// D/C & Reset pins: D/C - PB5, Reset - PB4
GPIOB->MODER |= GPIO_MODER_MODER4_O | GPIO_MODER_MODER5_O;
}
void spi_setup(){
/* Enable the peripheral clock of GPIOA */
RCC->AHBENR |= RCC_AHBENR_GPIOAEN;
/* (1) Select AF mode (10) on PA5, PA7, push-pull @PA4. MISO disabled (simplex mode)*/
/* (2) AF0 for SPI1 signals */
GPIOA->MODER = (GPIOA->MODER
& ~(GPIO_MODER_MODER4 | GPIO_MODER_MODER5 | \
GPIO_MODER_MODER7))\
| (GPIO_MODER_MODER4_O | GPIO_MODER_MODER5_AF |\
GPIO_MODER_MODER7_AF); /* (1) */
GPIOA->AFR[0] = (GPIOA->AFR[0] & \
~(GPIO_AFRL_AFRL5 | GPIO_AFRL_AFRL7)); /* (2) */
/* Enable the peripheral clock SPI1 */
RCC->APB2ENR |= RCC_APB2ENR_SPI1EN;
/* Configure SPI1 in master */
/* (1) Master selection, BR: Fpclk/256, software SS management
CPOL and CPHA at zero (rising first edge) */
/* (2) Slave select output disabled, 8-bit Rx fifo */
/* (3) Enable SPI1 */
SPI1->CR1 = SPI_CR1_MSTR | SPI_CR1_BR | SPI_CR1_SSM | SPI_CR1_SSI; /* (1) */
SPI1->CR2 = SPI_CR2_FRXTH | SPI_CR2_DS_2 | SPI_CR2_DS_1 | SPI_CR2_DS_0; /* (2) */
SPI1->CR1 |= SPI_CR1_SPE; /* (3) */
CS_HI(); RST_HI();
}
void i2c_setup(I2C_SPEED speed){
I2C1->CR1 = 0;
#if I2CPINS == A9A10
/*
* GPIO Resources: I2C1_SCL - PA9, I2C1_SDA - PA10
* GPIOA->AFR[1] AF4 -- GPIOA->AFR[1] &= ~0xff0, GPIOA->AFR[1] |= 0x440
*/
RCC->AHBENR |= RCC_AHBENR_GPIOAEN; // clock
GPIOA->AFR[1] &= ~0xff0; // alternate function F4 for PA9/PA10
GPIOA->AFR[1] |= 0x440;
GPIOA->MODER &= ~(GPIO_MODER_MODER9 | GPIO_MODER_MODER10);
GPIOA->MODER |= GPIO_MODER_MODER9_AF | GPIO_MODER_MODER10_AF; // alternate function
GPIOA->OTYPER |= GPIO_OTYPER_OT_9 | GPIO_OTYPER_OT_10; // opendrain
//GPIOA->OTYPER |= GPIO_OTYPER_OT_10; // opendrain
#else // undefined
#error "Not implemented"
#endif
// I2C
RCC->APB1ENR |= RCC_APB1ENR_I2C1EN; // timing
RCC->CFGR3 |= RCC_CFGR3_I2C1SW; // use sysclock for timing
if(speed == LOW_SPEED){ // 10kHz
// PRESC=B, SCLDEL=4, SDADEL=2, SCLH=0xC3, SCLL=0xC7
//I2C1->TIMINGR = (0xB<<28) | (4<<20) | (2<<16) | (0xC3<<8) | (0xC7);
I2C1->TIMINGR = (0xB<<28) | (4<<20) | (2<<16) | (0xC3<<8) | (0xB0);
}else{ // 100kHz
// Clock = 6MHz, 0.16(6)us, need 5us (*30)
// PRESC=4 (f/5), SCLDEL=0 (t_SU=5/6us), SDADEL=0 (t_HD=5/6us), SCLL,SCLH=14 (2.(3)us)
//I2C1->TIMINGR = (4<<28) | (14<<8) | (14); // 0x40000e0e
I2C1->TIMINGR = (0xB<<28) | (4<<20) | (2<<16) | (0x12<<8) | (0x11);
}
I2C1->CR1 = I2C_CR1_PE;// | I2C_CR1_RXIE; // Enable I2C & (interrupt on receive - not supported yet)
}