fb11e647
 vrobic
reseau statique a...
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
|
/*
* Copyright (C) 2014 Freie Universitรคt Berlin
*
* This file is subject to the terms and conditions of the GNU Lesser General
* Public License v2.1. See the file LICENSE in the top level directory for more
* details.
*/
/**
* @ingroup cpu_stm32f0
* @{
*
* @file
* @brief Low-level GPIO driver implementation
*
* @author Hauke Petersen <mail@haukepetersen.de>
*
* @}
*/
#include "cpu.h"
#include "periph/gpio.h"
#include "periph_conf.h"
/**
* @brief The STM32F0 family has 16 external interrupt lines
*/
#define EXTI_NUMOF (16U)
/**
* @brief Allocate memory for one callback and argument per EXTI channel
*/
static gpio_isr_ctx_t isr_ctx[EXTI_NUMOF];
/**
* @brief Extract the port base address from the given pin identifier
*/
static inline GPIO_TypeDef *_port(gpio_t pin)
{
return (GPIO_TypeDef *)(pin & ~(0x0f));
}
/**
* @brief Extract the port number form the given identifier
*
* The port number is extracted by looking at bits 10, 11, 12, 13 of the base
* register addresses.
*/
static inline int _port_num(gpio_t pin)
{
return ((pin >> 10) & 0x0f);
}
/**
* @brief Extract the pin number from the last 4 bit of the pin identifier
*/
static inline int _pin_num(gpio_t pin)
{
return (pin & 0x0f);
}
int gpio_init(gpio_t pin, gpio_mode_t mode)
{
GPIO_TypeDef *port = _port(pin);
int pin_num = _pin_num(pin);
/* enable clock */
periph_clk_en(AHB, (RCC_AHBENR_GPIOAEN << _port_num(pin)));
/* set mode */
port->MODER &= ~(0x3 << (2 * pin_num));
port->MODER |= ((mode & 0x3) << (2 * pin_num));
/* set pull resistor configuration */
port->PUPDR &= ~(0x3 << (2 * pin_num));
port->PUPDR |= (((mode >> 2) & 0x3) << (2 * pin_num));
/* set output mode */
port->OTYPER &= ~(1 << pin_num);
port->OTYPER |= (((mode >> 4) & 0x1) << pin_num);
/* finally set pin speed to maximum and reset output */
port->OSPEEDR |= (3 << (2 * pin_num));
port->BRR = (1 << pin_num);
return 0;
}
int gpio_init_int(gpio_t pin, gpio_mode_t mode, gpio_flank_t flank,
gpio_cb_t cb, void *arg)
{
int pin_num = _pin_num(pin);
int port_num = _port_num(pin);
/* set callback */
isr_ctx[pin_num].cb = cb;
isr_ctx[pin_num].arg = arg;
/* enable clock of the SYSCFG module for EXTI configuration */
periph_clk_en(APB2, RCC_APB2ENR_SYSCFGCOMPEN);
/* initialize pin as input */
gpio_init(pin, mode);
/* enable global pin interrupt */
if (pin_num < 2) {
NVIC_EnableIRQ(EXTI0_1_IRQn);
}
else if (pin_num < 4) {
NVIC_EnableIRQ(EXTI2_3_IRQn);
}
else {
NVIC_EnableIRQ(EXTI4_15_IRQn);
}
/* configure the active flank */
EXTI->RTSR &= ~(1 << pin_num);
EXTI->RTSR |= ((flank & 0x1) << pin_num);
EXTI->FTSR &= ~(1 << pin_num);
EXTI->FTSR |= ((flank >> 1) << pin_num);
/* enable specific pin as exti sources */
SYSCFG->EXTICR[pin_num >> 2] &= ~(0xf << ((pin_num & 0x03) * 4));
SYSCFG->EXTICR[pin_num >> 2] |= (port_num << ((pin_num & 0x03) * 4));
/* clear any pending requests */
EXTI->PR = (1 << pin);
/* unmask the pins interrupt channel */
EXTI->IMR |= (1 << pin);
return 0;
}
void gpio_init_af(gpio_t pin, gpio_af_t af)
{
GPIO_TypeDef *port = _port(pin);
uint32_t pin_num = _pin_num(pin);
/* set pin to AF mode */
port->MODER &= ~(3 << (2 * pin_num));
port->MODER |= (2 << (2 * pin_num));
/* set selected function */
port->AFR[(pin_num > 7) ? 1 : 0] &= ~(0xf << ((pin_num & 0x07) * 4));
port->AFR[(pin_num > 7) ? 1 : 0] |= (af << ((pin_num & 0x07) * 4));
}
void gpio_init_analog(gpio_t pin)
{
/* enable clock, needed as this function can be used without calling
* gpio_init first */
periph_clk_en(AHB, (RCC_AHBENR_GPIOAEN << _port_num(pin)));
/* set to analog mode */
_port(pin)->MODER |= (0x3 << (2 * _pin_num(pin)));
}
void gpio_irq_enable(gpio_t pin)
{
EXTI->IMR |= (1 << _pin_num(pin));
}
void gpio_irq_disable(gpio_t pin)
{
EXTI->IMR &= ~(1 << _pin_num(pin));
}
int gpio_read(gpio_t pin)
{
if (_port(pin)->MODER & (0x3 << (_pin_num(pin) * 2))) {
return _port(pin)->ODR & (1 << _pin_num(pin));
}
else {
return _port(pin)->IDR & (1 << _pin_num(pin));
}
}
void gpio_set(gpio_t pin)
{
_port(pin)->BSRR = (1 << _pin_num(pin));
}
void gpio_clear(gpio_t pin)
{
_port(pin)->BRR = (1 << _pin_num(pin));
}
void gpio_toggle(gpio_t pin)
{
if (gpio_read(pin)) {
_port(pin)->BRR = (1 << _pin_num(pin));
} else {
_port(pin)->BSRR = (1 << _pin_num(pin));
}
}
void gpio_write(gpio_t pin, int value)
{
if (value) {
_port(pin)->BSRR = (1 << _pin_num(pin));
} else {
_port(pin)->BRR = (1 << _pin_num(pin));
}
}
void isr_exti(void)
{
/* only generate interrupts against lines which have their IMR set */
uint32_t pending_isr = (EXTI->PR & EXTI->IMR);
for (size_t i = 0; i < EXTI_NUMOF; i++) {
if (pending_isr & (1 << i)) {
EXTI->PR = (1 << i); /* clear by writing a 1 */
isr_ctx[i].cb(isr_ctx[i].arg);
}
}
cortexm_isr_end();
}
|