Dear Members,
Where can I find from software development kit the example for writing and reading from I2C EEPROM ?
Thanks
Dear Members,
Where can I find from software development kit the example for writing and reading from I2C EEPROM ?
Thanks
An I2C EEPROM neither knows nor cares what microcontroller you use; all it sees is the transactions on the I2C bus - Start Conditions, Addressing, Stop Conditions; ACK/NAK, etc.
The Nordic SDK examples show you how to use the I2C (aka "TWI") hardware in the nRF52 - ie how to address a Slave, Read, and Write.
So you use the basic functions, together with the datasheet of your EEPROM, to generate the I2C transactions that the EEPROM requires.
For examples, see:
There are 4 TWI examples
which one is the closest application with I2C EEPROM ?
This one
nRF5_SDK_17.0.2_d674dde\examples\peripheral\twi_master_with_twis_slave\pca10056\blank\arm5_no_packs ?
thanks
Have you used an oscilloscope or analyser to see what's happening on the wires?
Ok, I'll see with analyzer and posted, thanks
I reckon, I have insufficient power for this 24C16 PU27, I will try with external 3.3V, I keep posted, thanks
from this code,
err_code = eeprom_write(addr, &clear_val, 1);
if (NRF_SUCCESS != err_code)
{
NRF_LOG_INFO("communication error 24C16.\r\n");
return;
}
how can I print out err_code ?
NRF_LOG_INFO("%u",err_code); ?
I got
nfo> app: Error code 33281
what's the meaning ?
I got
nfo> app: Error code 33281
what's the meaning ?
The error code corresponds to NRF_ERROR_DRV_TWI_ERR_ANACK, which indicates that it received a NACK when it tried to address the sensor. There can be several reasons for this to happen. You should probably verify the communcation with the TWI scanner example first, as Awneil suggested.
TWI scanner result :
I can not see 24C16 address
Is it conflict between my LCD and 24C16 ?
Is it conflict
As always, it's important to start simple; solve one problem at a time - don't leap straight into a whole pile of potential problems!
https://www.avrfreaks.net/forum/help-it-doesnt-work
So start with just the EEPROM on the bus - nothing else.
I can write it,
but it's not complete , is it related with timing ?
The output when reading
nfo> app: 7E0:
nfo> app: 07
nfo> app: 07
nfo> app: 07
nfo> app: 07
nfo> app: 07
nfo> app: 07
nfo> app: 07
nfo> app: 07
nfo> app: 07
nfo> app: 07
nfo> app: 07
nfo> app: 07
nfo> app: 07
nfo> app: 07
nfo> app: 07
nfo> app: AD
I want to write al 0xAD but only the end is AD ??
Code :
* Function uses the TWI interface to write data into EEPROM memory.
*
* @param addr Start address to write.
* @param[in] pdata Pointer to data to send.
* @param size Byte count of data to send.
* @attention Maximum number of bytes that may be written is @ref EEPROM_SEQ_WRITE_MAX.
* In sequential write, all data must be in the same page
* (higher address bits do not change).
*
* @return NRF_SUCCESS or reason of error.
*
* @attention If you wish to communicate with real EEPROM memory chip, check its readiness
* after writing the data.
*/
static ret_code_t eeprom_write(uint16_t addr, uint8_t const * pdata, size_t size)
{
ret_code_t ret;
/* Memory device supports only a limited number of bytes written in sequence */
if (size > (EEPROM_SEQ_WRITE_MAX_BYTES))
{
return NRF_ERROR_INVALID_LENGTH;
}
/* All written data must be in the same page */
if ((addr / (EEPROM_SEQ_WRITE_MAX_BYTES)) != ((addr + size - 1) / (EEPROM_SEQ_WRITE_MAX_BYTES)))
{
return NRF_ERROR_INVALID_ADDR;
}
do
{
nrf_delay_ms(25);
uint8_t buffer[EEPROM_ADDRESS_LEN_BYTES + EEPROM_SEQ_WRITE_MAX_BYTES]; /* Addr + data */
memcpy(buffer, &addr, EEPROM_ADDRESS_LEN_BYTES);
memcpy(buffer + EEPROM_ADDRESS_LEN_BYTES, pdata, size);
ret = nrf_drv_twi_tx(&m_twi_master, EEPROM_ADDR, buffer, size + EEPROM_ADDRESS_LEN_BYTES, false);
}while (0);
return ret;
}
void eeprom_cmd_clear()
{
uint8_t clear_val = 0xAD;
size_t addr;
for (addr = 0; addr <EEPROM_SIZE; ++addr)
{
ret_code_t err_code;
err_code = eeprom_write(addr, &clear_val, 1);
if (NRF_SUCCESS != err_code)
{
NRF_LOG_INFO("communication error 24C16 By Rixtronix LAB.\r\n");
NRF_LOG_INFO("Error code %u",err_code);
return;
}
NRF_LOG_INFO("CLEARING 24C16 By Rixtronix LAB...\r\n");
}
NRF_LOG_INFO("FINISHED CLEARING 24C16 By Rixtronix LAB.\r\n");
}
What do I miss here ?
Thanks
#define EEPROM_SEQ_WRITE_MAX_BYTES 200 #define EEPROM_ADDR 0x50 #define EEPROM_ADDRESS_LEN_BYTES 2 #define EEPROM_SIZE (2048u) //!< 24C16 EEPROM size. #define MASTER_TWI_INST 0 //!< TWI interface used as a master accessing EEPROM memory. #define IN_LINE_PRINT_CNT (16u) //!< Number of data bytes printed in a single line.