NRF9160 SPI: Spikes on MISO and CS lineshttps://devzone.nordicsemi.com/f/nordic-q-a/85513/nrf9160-spi-spikes-on-miso-and-cs-linesHello, we are connecting an NRF9160 with a WFM200 wifi chip over SPI using Zephyr RTOS. Additionally, we manually control the chip select pin in the driver code for the wifi module. During the communication we are frequently receiving spikes on theen-USTelligent Community 13Mon, 07 Mar 2022 16:00:32 GMTRE: NRF9160 SPI: Spikes on MISO and CS lineshttps://devzone.nordicsemi.com/thread/356689?ContentTypeID=1Mon, 07 Mar 2022 16:00:32 GMT137ad170-7792-4731-bb38-c0d22fbe4515:11c281b1-0fc3-454d-958e-e8a58bb36ae1Nils Ruf<p>Thanks for the quick reply. I will look into this...</p><div style="clear:both;"></div>RE: NRF9160 SPI: Spikes on MISO and CS lineshttps://devzone.nordicsemi.com/thread/356591?ContentTypeID=1Mon, 07 Mar 2022 12:52:35 GMT137ad170-7792-4731-bb38-c0d22fbe4515:6c88e3a8-8f66-4412-9d86-bea3e8ddaf89Kenneth<p>Looks like some noise on the MISO line, this pin is driven by the peer (wifi chip). I suspect there is some volage/current &quot;bounce back&quot;, in lack of a better word, due to inductance or capacitance in wires or similiar, I suggest to improve grounding between the boards, and also place the SPI wires and ground wire(s) close together, possible shorten them also. This is an electrical hardware problem, not related to software.</p> <p>Best regards,<br />Kenneth</p><div style="clear:both;"></div>