Regarding twi sensor

[Manoj Hiwarkar]

Dear Sir,

I am using nrf52832 & sdk 14. When I dump your twi sensor code(SDK14\nRF5_SDK_14.2.0_17b948a\examples\peripheral\twi_scanner\pca10040\blank\arm5_no_packs) in the nrf52832 development kit there is no activity observed on the oscilloscope on the pins SCL(P0.27) & SDA(P0.26).

But when I tried the same thing on nrf51422, I got the clock pulses. 

So please tell me what is the problem with the nrf52832 & sdk 14 (I have tried this with sdk12 also).

Regards,

Manoj Hiwarkar.

[MartinBL]

Hi,

As long as you haven't modified anything, the scanner example and the PCA10040 should work out of the box. Have you double checked that you are using the correct pins? The default pins are configured in pca10040.h as:

#define ARDUINO_SCL_PIN             27    // SCL signal pin
#define ARDUINO_SDA_PIN             26    // SDA signal pin

which should be correct in your case. 

Have you connecte anything else than your scope to the pins?

[Manoj Hiwarkar]

No, I have not modified anything, the scl & sda pins are defined exactly as shown above. And I have also not connected anything other than DSO pins.

[MartinBL]

Are you able to toggle the pins with minimal code (without using TWI)?

[Manoj Hiwarkar]

yes

[MartinBL]

That is strange.

Have you tried to route the TWI to other pins on the DK? Pin 3 and 4 for example? They are my go-to TWI pins as they are not connected to any buttons or LEDs etc. on the kit. 

Can you compile a fresh twi_scanner example with default pins etc., so that I can test the same code on my own development kit?

[Manoj Hiwarkar]

Ok how shall i send the project file to you?

[MartinBL]

You can just upload it here. In the comment "input field" click Insert -> Insert Image/Video/File and choose 'File Upload'. 

DId you try different pins? And by the way, do you have another kit you can try?

[Manoj Hiwarkar]

1.Yes I have tried with P0.24 & P0.25.

2. We have our target board , but we don't have another kit.

[Manoj Hiwarkar]

twi_scanner.rar

Here is the twi scanner file. please check

[MartinBL]

I tested your code and it worked out of the box. I used 

• An MPU9255 as slave (shouldn't matter though as long as you have functional slave device?)
• PCA10040 development kit
• SDK 14.2.0
• And these pins:

#define ARDUINO_SCL_PIN             27    // SCL signal pin
#define ARDUINO_SDA_PIN             26    // SDA signal pin

I have attached my .hex file. Can you try to program it to your kit and see if it works? If it doesn't, then your kit, or possibly any attached slave devices, seems to be broken. I have seen other cases where things work on my system, but not on the customer's, and in one particular case it turned out that the customer had changed his driver files and forgotten about it. Hence, it worked when I compiled the code with my original SDK files, but not when he compiled it with his modified files. So make sure to use original drivers. 

[Manoj Hiwarkar]

The twi sensor code is working now. The problem was in pack installation. But now the thing is I am not able to configure the pins P0.09 & P0.10 as SCL & SDA. Other pins are getting configured. 

[Manoj Hiwarkar]

I am getting the clock pulses on SCL & SDA  pins of the target board. But still I am not getting the data from the max30205. I am herewith uploading the two videos (both are with different time base) these clock pulses on the oscilloscope. 

Blue line is SDA 

Yellow line is SCL

So please tell me where I am going wrong.