Why can not read twi data ? twi interfacing with RTC DS1307....

[chchoi]

Why can not read twi data ? at nrf52832 chip.... but Read well in Arduino....

twi interfacing with RTC DS1307....

please give me some hint.....

1. nrf_drv_config.h

   #define TWI0_ENABLED 1 #define TWI1_ENABLED 1

2. define

   #define DS1307_I2C_SCL_PIN 9 // 9 #define DS1307_I2C_SDA_PIN 10 // 10

   #define DS1307_ADDR 0x68U //I2C ADDR 0x68U

   void twi_handler(nrf_drv_twi_evt_t const * p_event, void * p_context) {
   switch(p_event->type) { case NRF_DRV_TWI_EVT_DONE: break; default: break; } }

   void twi_init (void) { ret_code_t err_code;

   const nrf_drv_twi_config_t    twi_ds1307_config = {
   	.scl                    = DS1307_I2C_SCL_PIN,
   	.sda                   = DS1307_I2C_SDA_PIN,
   	.frequency          = NRF_TWI_FREQ_100K,
   	.interrupt_priority = APP_IRQ_PRIORITY_HIGH
   };
   
   err_code = nrf_drv_twi_init(&m_twi_ds1307, &twi_ds1307_config, twi_handler, NULL);  		
   APP_ERROR_CHECK(err_code);
   
   nrf_drv_twi_enable(&m_twi_ds1307);
   

   }

3. reading.....

   uint8_t r_buf[16]={0,}; err_code = nrf_drv_twi_rx(&m_twi_ds1307, DS1307_ADDR, r_buf, sizeof(r_buf)); APP_ERROR_CHECK(err_code);

   for (uint32_t i = 0; i < 16; i++) { printf("%d = 0x%02X \n",i, r_buf[i] ); }

4. result

1 = 0x00 2 = 0x00 ... 15 = 0x00

all value zero....

[chchoi]

I have finally read the data.

DS1337 Get Time. twi_i2c_read_err 0, 0 ,[00]

0 = 0x38
1 = 0x42
2 = 0x3A
3 = 0x88
4 = 0x23
5 = 0x47
6 = 0x17
7 = 0x70
8 = 0x7E
9 = 0xF7
10 = 0xE9
11 = 0x23
12 = 0xC1
13 = 0x78
14 = 0x67
15 = 0x37

The reason I could not read it was because I read sda scl using only battery power. I can read the data after connecting 3.2v power to VCC, GND in DS1307.

Thank you for your response. I would appreciate it if you could give me a place to refer to how to convert from buffer data to date and time data.

[MartinBL]

We don't have examples or code for that around here, but if you google something like "dS1307 c library" i'm sure you will find some tips.