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lib/i2c.c use dwt.h 

Signed-off-by: surenyi <surenyi82@163.com>
master
surenyi 6 years ago
parent
7edbcc24a8
commit
23821a1c8b
6 changed files with 119 additions and 38 deletions
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  1. 2
      lib/at24c256_i2c.c
  2. 10
      lib/dwt.h
  3. 131
      lib/i2c.c
  4. 2
      lib/i2c.h
  5. 6
      lib/stdio_ymodem.c
  6. 2
      targets/stm32f429-disc/main.c

2
lib/at24c256_i2c.c
View File

@ -12,7 +12,7 @@ static int _is_16bits = 0;
int at24_i2c_init(uint32_t scl, uint32_t sda, uint8_t addr, int bits)
{
_i2c = i2c_new(scl, sda);
_i2c = i2c_new(scl, sda, 100000); /* 100K */
_address = addr;
_is_16bits = bits;
return 0;

10
lib/dwt.h
View File

@ -4,8 +4,9 @@
#ifdef __cplusplus
extern "C" {
#endif
#include <stdint.h>
extern unsigned int SystemCoreClock;
extern uint32_t SystemCoreClock;
#define DWT_CR (*(volatile unsigned int *)0xE0001000)
#define DWT_CYCCNT (*(volatile unsigned int *)0xE0001004)
@ -13,6 +14,13 @@ extern unsigned int SystemCoreClock;
#define DEM_CR_TRCENA (1 << 24)
#define DWT_CR_CYCCNTENA (1 << 0)
static inline int __attribute__((unused)) dwt_is_enabled(void)
{
if (DEM_CR & DEM_CR_TRCENA)
return 1;
return 0;
}
static inline void __attribute__((unused)) dwt_init(void)
{
DEM_CR |= DEM_CR_TRCENA; /* enable DWT */

131
lib/i2c.c
View File

@ -2,7 +2,7 @@
#include "stm32f4xx.h"
#include "gpio.h"
#include "i2c.h"
#include "utils.h"
#include "dwt.h"
struct i2c {
GPIO_TypeDef *scl_port;
@ -10,6 +10,8 @@ struct i2c {
GPIO_TypeDef *sda_port;
uint32_t sda;
unsigned int ticks;
};
#define DELAY_TICKS (4)
@ -23,7 +25,7 @@ extern GPIO_TypeDef *gpio_port(uint32_t pin);
#define SCL_IN(i2c) ((((i2c)->scl_port)-IDR) & (((i2c)->sda) & PIN_MASK))
#define SDA_IN(i2c) ((((i2c)->sda_port)->IDR) & (((i2c)->sda) & PIN_MASK))
i2c_t i2c_new(uint32_t scl, uint32_t sda)
i2c_t i2c_new(uint32_t scl, uint32_t sda, int speed)
{
i2c_t i2c = malloc(sizeof *i2c);
if (i2c == NULL) {
@ -40,6 +42,12 @@ i2c_t i2c_new(uint32_t scl, uint32_t sda)
SCL_H(i2c);
SDA_H(i2c);
if (speed > 0) {
i2c->ticks = 1000000 / speed / 2;
} else {
i2c->ticks = DELAY_TICKS;
}
return (i2c);
}
@ -50,118 +58,169 @@ void i2c_free(i2c_t i2c)
int i2c_start(i2c_t i2c)
{
int en, err = 0;
if (!(en = dwt_is_enabled())) {
dwt_init();
}
SDA_H(i2c);
SCL_H(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
if (!SDA_IN(i2c)) { /* sda busy ? */
return -1;
err = -1;
goto err;
}
SDA_L(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
if (SDA_IN(i2c)) { /* sda hi, error. */
return -2;
err = -2;
goto err;
}
SDA_L(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
return 0;
err:
if (!en) {
dwt_close();
}
return err;
}
void i2c_stop(i2c_t i2c)
{
int en;
if (!(en = dwt_is_enabled())) {
dwt_init();
}
SCL_L(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
SDA_L(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
SCL_H(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
SDA_H(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
if (!en) {
dwt_close();
}
}
void i2c_ack(i2c_t i2c)
{
int en;
if (!(en = dwt_is_enabled())) {
dwt_init();
}
SCL_L(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
SDA_L(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
SCL_H(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
SCL_L(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
if (!en) {
dwt_close();
}
}
void i2c_nack(i2c_t i2c)
{
int en;
if (!(en = dwt_is_enabled())) {
dwt_init();
}
SCL_L(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
SDA_H(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
SCL_H(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
SCL_L(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
if (!en) {
dwt_close();
}
}
int i2c_wait_ack(i2c_t i2c)
{
int err;
int en, err;
if (!(en = dwt_is_enabled())) {
dwt_init();
}
SCL_L(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
SDA_H(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
SCL_H(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
err = SDA_IN(i2c);
SCL_L(i2c);
if (!en) {
dwt_close();
}
return err;
}
int i2c_send_byte(i2c_t i2c, uint8_t byte)
{
int i = 8;
int en, i = 8;
if (!(en = dwt_is_enabled())) {
dwt_init();
}
while(i--) {
SCL_L(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
if(byte & 0x80)
SDA_H(i2c);
@ -170,21 +229,28 @@ int i2c_send_byte(i2c_t i2c, uint8_t byte)
byte <<= 1;
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
SCL_H(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
}
SCL_L(i2c);
if (!en) {
dwt_close();
}
return 0;
}
uint8_t i2c_recv_byte(i2c_t i2c)
{
int i = 8;
int en, i = 8;
uint8_t rd = 0;
if (!(en = dwt_is_enabled())) {
dwt_init();
}
SDA_H(i2c);
while(i--) {
@ -192,17 +258,20 @@ uint8_t i2c_recv_byte(i2c_t i2c)
SCL_L(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
SCL_H(i2c);
delay_microseconds(DELAY_TICKS);
dwt_wait_us(i2c->ticks);
if (SDA_IN(i2c)) {
rd |= 0x01;
}
}
SCL_L(i2c);
if (!en) {
dwt_close();
}
return (rd);
}

2
lib/i2c.h
View File

@ -7,7 +7,7 @@ extern "C" {
typedef struct i2c *i2c_t;
i2c_t i2c_new(uint32_t scl, uint32_t sda);
i2c_t i2c_new(uint32_t scl, uint32_t sda, int speed);
void i2c_free(i2c_t);

6
lib/stdio_ymodem.c
View File

@ -54,7 +54,7 @@ int stdio_ymodem_recv(void *user,
int (*_on_info)(void *user, const char *name, unsigned int size),
int (*_on_data)(void *user, const void *data, unsigned int len))
{
int err;
int err, en;
struct stdio_ymodem modem = {
.xfer = {
.getc = do_getc,
@ -67,9 +67,13 @@ int stdio_ymodem_recv(void *user,
.user = user
};
if (!(en = dwt_is_enabled())) {
dwt_init();
}
err = ymodem_recv(&modem.xfer);
if (!en) {
dwt_close();
}
return (err);
}

2
targets/stm32f429-disc/main.c
View File

@ -133,7 +133,7 @@ int main()
iis_setup(&i2s0, IIS_STD_PHILIP, 44100);
iis_set_tx_completion(&i2s0, tx_done, NULL);
i2c = i2c_new(PB6, PB7);
i2c = i2c_new(PB6, PB7, 100000);
wm8978_init_with_i2c(i2c);

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