ENV shield + GPS shield not working

Looking to see if anybody has some quick thoughts before I look into digging further...

I've got a MKR WiFi 1010. I've got an ENV shield on it. I've also got a GPS shield connected via I2C cable. Power is coming from laptop USB (no battery yet).

Without the ENV shield attached, I'm able to get GPS location just fine. When I attach the ENV shield, however, I can no longer get GPS location. It seems to initialize fine (according to serial monitor). It just never has location available. I'm running the GPSLocationStandby example (no modifications). The ENV is a planned enhancement, but I'm not doing anything with it at the moment.

Am I asking too much of laptop USB power? (Hoping that's the answer.) I haven't gotten a battery yet, but that's coming soon.

Any conflict between the 2 boards? For my project, I guess it's not the end of the world if I don't get temperature data and such, but I was at a very minimum hoping to make use of the SD card on it!

Is there something I'm missing there by not performing any initialization at all yet with the ENV board? It's literally just sitting there doing nothing at the moment (until I get this figured out).

Any thoughts/suggestions? Thanks!

Following this as well! I am hoping to stack these shields for a future project so I hope yours starts working!


So, through lots of trial and error through many combinations, I did find a working setup for this. Here’s the conclusion I came to: When using the GPS shield in addition to the ENV shield, the GPS module just does not like going into standby mode (standby()). My test basically boiled down to the GPSLocationStandby example for the MKR GPS library. I know that even without the extra ENV shield, way back when (and not realizing it was related), I was having issues (sometimes) with looping through wakeup and standby mode. It just seems like even when it does work, you have to “kick” it A LOT (available()).

Anyway, figured I’d give an update. I don’t have any explanation on what the root issue is there. I don’t plan to investigate it further. I have something that works for me. I’m basically abandoning standby mode. I don’t have a good feel for how that will affect power consumption. At the moment, I’ve settled on a 1ms available() poll loop (no standby).

If anybody ever has any further details, I’ll definitely be watching.

Other than that, the combo (GPS+ENV) works great! I do recommend the little watch battery for the GPS shield. Finding location after boot up is much quicker (although, it’s honestly not horrible to begin with). Location performance seems pretty good.

Also, FWIW, different battery (LiPo) combinations were also in my test (thinking it might be a power issue). That didn’t seem to make a difference. Having said that, knowing what I know that, that may have been inconclusive (but I don’t suspect it). At the time, I didn’t have a test that used standby that didn’t seen serial (USB) connected.

I'm trying to do the same thing. I can get each of these shields (GPS and ENV) to work independently with the MKR WiFi 1010, but I can't get them to collect data together in the same sketch. Any help pointing me in the correct direction would certainly be appreciated.