How to resolve NRF_ERROR_INTERNAL error in TWI communication?

RE: How to resolve NRF_ERROR_INTERNAL error in TWI communication?

Hung Bui — Wed, 27 Apr 2016 08:29:16 GMT

Hi Naveen,

Glad that you found the issue. Yeah, I2C on the nRF51 doesn't really support multiple master mode which require arbitration logic and busy detection.

RE: How to resolve NRF_ERROR_INTERNAL error in TWI communication?

naveen — Tue, 26 Apr 2016 13:57:10 GMT

Hi Hung Bui,

Thanks for your valuable responses,

Now read and write is working fine without any error.

In previous setup slave is connected to one more master, now we connected that slave to nordic master alone.

Thanks regards, -Naveen

RE: How to resolve NRF_ERROR_INTERNAL error in TWI communication?

Hung Bui — Tue, 19 Apr 2016 15:50:54 GMT

It's strange, Naveen. What is the supply voltage ?

The SCL, SDA when not in transaction should retain the voltage level of at least 0.7VDD. A photo of your setup could help a little bit.

I suspect there could be something wrong with the sensor. If you don't connect the pin to the sensor, could you try to monitor the pin ? (of course it can only transmit the address because of no ACK, but we can still can see if it can transmit properly).

In your "OTHER_MASTER" trace, I can also see that the pins are pulled low, this is not normal. When the pins are connected to pullup resistors, they should be high between transaction.

RE: How to resolve NRF_ERROR_INTERNAL error in TWI communication?

naveen — Tue, 19 Apr 2016 14:34:09 GMT

Hi Hung Bui,

We didn't remove internel pull up. If we use only internel pull up, the maximum SCL & SDA value is 1.7V & 1.9V respectively.Are we supposed to receive the above mentioned voltage values for the SCL and SDA pins or it should be different ? Moreover we didnt see any output with only internal pull up in DSO so we decided to add an external pull up(10K).

For each write i'm sending 5 bytes, i didn't use SUSPEND task. Even i'm not sure why there is gap between each bytes transfer. when transaction is finished, SCL & SDA pins are not going high (In twi_master_with_twis_slave example after transaction SCL & SDA pins goes high).

Note : SCL connected to P0.03 SDA connected to P0.04

Thanks Regards, -Naveen

RE: How to resolve NRF_ERROR_INTERNAL error in TWI communication?

Hung Bui — Tue, 19 Apr 2016 11:50:53 GMT

I assume you used the external pullup resistors, have you removed the internal pull up when configuring TWI ? By default we use internal pullup for the TWI pins with the twi driver.

It's not very clear for me, from your trace, there is no STOP condition but there are gaps between each byte, does that mean you used SUSPEND task? When you finish a transaction would the pins go high up ?

RE: How to resolve NRF_ERROR_INTERNAL error in TWI communication?

naveen — Tue, 19 Apr 2016 09:49:43 GMT

Hi Hung Bui,

Thanks for your responses,

Transaction is not yet completed that’s why its low, whatever i sent above (probed pics) that’s for single write but i'm doing multiple writes so its showing low state.

we are using fuel gauge sensor, Please find the data-sheet and circuit diagram (Figure-1) in below link.

www.onsemi.com/.../LC709203F-D.PDF

we verified the twi_master_with_twis_slave example, its fine.

Thanks Regards, -Naveen

RE: How to resolve NRF_ERROR_INTERNAL error in TWI communication?

Hung Bui — Tue, 19 Apr 2016 08:42:48 GMT

Hi Naveen,

If the TWI slave NACK, then on the master we will receive NRF_TWI_EVENT_ERROR and in the application it will be resulted as NRF_ERROR_INTERNAL.

It's a little bit strange in your probe trace that the SDA and SCL were held low when finished transaction, it should be high as the pins are pulled up. I assume that the slave held them low. Could you send the schematic ? Also please update the datasheet of the sensor you used.

Have you tried to test with the twi_master_with_twis_slave example, just to verify the normal behaviour of the nRF52 and TWIS+TWIM ?

RE: How to resolve NRF_ERROR_INTERNAL error in TWI communication?

naveen — Mon, 18 Apr 2016 15:27:13 GMT

Hi Hung Bui,

The "twi_tx_start_transfer" function is throwing "NRF_ERROR_INTERNAL" error.

I enabled debug prints in "twi_tx_start_transfer" and "twi_transfer" functions.

In success case (with delay for each read and write) "twi_transfer" function returned false condition after writing all bytes (NRF_TWI_EVENT_STOPPED is stopped).

In Failure case (without delay) "twi_transfer" function returned true condition continuously, so its hangs.

May i know how to resolve this issue ?

Thanks regards, -Naveen

RE: How to resolve NRF_ERROR_INTERNAL error in TWI communication?

Hung Bui — Thu, 14 Apr 2016 12:08:26 GMT

Hi Naveen,

Could you track down and find which function threw the "NRF_ERROR_INTERNAL" error ? Could you try to use the TWI directly and skip the driver, just to send or receive a few bytes.

If you send 2-3 bytes at a time in one packet what the signal would be?