Problem in the reading of CO value with the board P-Nucleo-IKA02A1

SGuar · ‎2018-10-01

I'm trying to work with P-Nucleo-IKA02A1 but I have some problems:

1) The data of CO that I take from the electronic circuit board with the software UNINUCLEO are not plausible. The value (made in ppm) is negative and, after a small physical pressure on the board, it changes to 2600 ppm more or less. Moreover the value doesn't change even if I create an initial fire on the transducer.

2) How can I send the data via BLE to an Android application?

Jiri HLADIK · ‎2018-10-02

Hello,

1) The negative ppm and values over 2600ppm are definitely wrong. Try to measure the voltage on the reference pin and on gas concentration reading pin. Both should be around 430mV. If you see Vcc on gas concentration pin, check if the jumper on JP2 is properly attached.

The board should not react on pressure. It can react on touches directly on sensor because in that case you induce some current into sensor and affect the reading for some time.

2) BLE supports a lot of different profiles which depends on application. So you need to select the profile you want, find android application which support that profile and then configure BLE stack. I recommend to use some example for X-NUCLEO-IDB board.

SGuar · ‎2018-10-05

Thank you for your support! I solved the problem connecting the jumper JP2.

Now we obtaine the right value of CO.

Regarding to the BLE connection, I have already used firmware ALLMEMS1 for the boards x-nucleo-iks01a2 and x nucleo idb05a1. Is there a symilar prepared firmware for the P-Nucleo-IKA02A1 in order to send data via BLE?

Thank you.