Hello! I am a newcomer to nrf and embedded programming (other than basic arduino and micropython projects). So far I have gone through many of the devacademy walkthroughs. What I want to do is simply implement central_uart and peripheral_uart on two nrf52840 dongles so I can use NUS to send messages back and forth between them. I already have my peripheral send messages to my phone's nrf connect app and this works well, however it is very basic (I wrote it myself with peripheral_nus example) so I want to transition to peripheral_uart. My first step was to get central_uart and/or peripheral_uart working on my dongles. I started with central_uart. However, when flashing it onto my device and looking at the log through the serial port I run into "<err> central_uart: uart_init failed (err -88). After adding some debugging messages into the uart_init function I find that the -88 error is coming from the "uart_callback_set" command. I am not sure how to remedy this, or if additional work needs to be done from the stock central_uart before I flash it onto my nrf 52840 dongle.
Other than debug messages and enabling them I have not edited the code from the stock.
Thoughts? Advice?