I was having some pretty annoying connectivity issues with my freshly out of the box iLogger, but I was able to solve them. It required an update to its FW (got it from iLogger setup instructions page) and additionally it did not seem to like the 16 gig SD card I had used. When I took a 32 gig card, formatted to 8 gigs, it started working pretty smoothly. CAN data, SD mount, all ok.
However, I am still having some issues with GPS connectivity. iLogger is not detecting my GPS. I have it hooked up to the GPS port:
M9N TX → iLogger GPS RX
M9N RX → iLogger GPS TX
The GPS unit is set to output NMEA data at 9600 bauds. It is a 5v device → is iLogger 5v tolerant?
Any instructions on how to debug the GPS? It gets a fix. I can also see it outputting NMEA data @ 9600 when I check with an FTDI USB to serial adapter.
Yep, bluetooth disconnect was fixed when I swapped the SD card to another one. I suppose the iLogger was freaking out when trying to mount / RW that 16 gig card. It was freshly formatted to FAT32, just like the new 32 gig card is (but only has a single 8 gig partition).
If your GPS pins directly connect to ESP32, then it should be 5v tolerant. The MRO M9N is a 5V powered device, so I hooked the power to CAN2 and UART to the iLogger GPS Port.
The GPS is this one. Pinout was not straightforward to get from mRobotics so I soldered the pins to the bottom side on pads that are labeled 5V, GND, GPS RX, GPS TX. My previous picture from RealTerm was read from the TX pin, so obviously my GPS side connection seems to be ok.
Thanks for the details. Actually that article is not that accurate, ESP32 pins are not tolerant to 5V, and if used, it would lead to unexpected behavior. So it is not recommended to use 5V input to it’s pins without at least proper protection like a resistor or a voltage divider. It might not damage it instantly, but it can lead to long-term degradation.
Now back to your GPS, I believe that it’s GPS RX and GPS TX pins are actually 3.3v. If you have a voltmeter, can you measure their voltage to ground pin? Even tho the module is powered by 5V, I think its regulated down to 3.3v before reaching the MCU.