Hi
Env: keil uvision 5 and SDK 9 and custome breakoutboard for nRF51822 (PTR5518: no external crystal) and no SD.
I am trying doing the first steps in twi over nRF51822, in a custom breakoutboard (PTR5518) without external crystal.
I have a TMP102 temp sensor connected to pins 9 (SDA) and 8(SCL)
I have copied the nrf_drv_config.h from components/nrf_drivers to my project root. I have done the following changes:
Desabled twi 1 and enabled twi 0:
#define TWI0_ENABLED 1
#if (TWI0_ENABLED == 1)
#define TWI0_CONFIG_FREQUENCY NRF_TWI_FREQ_100K
#define TWI0_CONFIG_SCL 8
#define TWI0_CONFIG_SDA 9
#define TWI0_CONFIG_IRQ_PRIORITY APP_IRQ_PRIORITY_HIGH
#define TWI0_INSTANCE_INDEX 0
#endif
and changed clock settings too:
/* CLOCK */
#define CLOCK_CONFIG_XTAL_FREQ NRF_CLOCK_XTALFREQ_16MHz
#define CLOCK_CONFIG_LF_SRC NRF_CLOCK_LF_SRC_RC
#define CLOCK_CONFIG_LF_RC_CAL_INTERVAL RC_500MS_CALIBRATION_INTERVAL
#define CLOCK_CONFIG_IRQ_PRIORITY APP_IRQ_PRIORITY_LOW
In the app:
#include <stdbool.h>
#include <stdint.h>
#include "nrf_delay.h"
#include "nrf_gpio.h"
#include "boards.h"
#include "nrf_drv_twi.h"
const nrf_drv_twi_t twi2 = NRF_DRV_TWI_INSTANCE(0);
uint32_t err_code;
uint8_t device_address = 0;
bool device_found = false;
void twi_init (void)
{
const nrf_drv_twi_config_t twi_config = {
.scl = 8,
.sda = 9,
.frequency = NRF_TWI_FREQ_100K,
.interrupt_priority = 3
};
err_code=nrf_drv_twi_init(&twi2,&twi_config,NULL); //Returns SUCCESS!
nrf_drv_twi_enable(&twi2);
}
int main(void)
{
nrf_gpio_cfg_output(19); //LED ON custom board
twi_init();
uint8_t dummy_data = 0x55;
for(uint8_t i = 0; i <= 0x7F; i++)
{
device_address = i;
nrf_drv_twi_tx(&twi2, i, &dummy_data, 1, false);
nrf_delay_ms(10);
}
if(device_found)
{
while(true)
{
nrf_gpio_pin_set(19);
nrf_delay_ms(100);
}
}
else
{
nrf_gpio_pin_clear(19);
while(true)
{
;
}
}
}
Device is never found. It seems that nrf_drv_twi_tx always return Internal_error.
Why? Could it be related with clock settings?
Any help would be very appreciated. Thank you
Alex
