Hi!
I'm trying to communicate with modem through UART.
Power supply: Battery connected to VDDH
VDD_nRF: 1.8V
nRF52840 DK connected to modem devkit using wires (about 10 cm length)
nRF receives data from modem, but modem don't see data. I don't know, if it nRF chip problem or no. I had connected oscilloscope to nRF tx pin and UART worked. I thought that I need pull-up or pull-down resistor, but it didn't help. I measured oscilloscope capacitance and setup same capacitance between rx pin and GND and it worked.
Could you explain, why it happens, and how to solve it? Adding capacitance doesn't seem a good solution.
