GSM GPRS GNSS Bluetooth HAT Module for Raspberry Pi, SIM868 Quad-Band GPS Tracker Expansion Board Compatible with Arduino, for SMS Call Data Transfer Navigation IoT Projects

Bought this product to integrate with a USSD based IoT platform, it does exactly what I needed with the added bonus (which isn't mentioned in the description) that I can switch the modem on using commands scripted from the Pi :-)

First of all, when I asked questions about the GPS PPS features of this board and the seller replied to say "not supported", they then deleted my question. Seems this is a bit of a 'thing' with Waveshare. And like many Waveshare products, out of the box they can take some work to get erm, working.I did get the GPS working, but when we query it with:cgps -sit often seems to send the board into a locked up state, requiring a reboot. So I get the GPS NMEA signal into the NTP server and use it that way - I don't query it directly as it doesn't seem to like it.Note: it has NO PPS support. The flashing LED says its PPS but that signal is not passed along through the UART so no access to it! Seems like a dumb oversight to me, but that's Waveshare.I haven't tested the full features of the board though, so look to others to give their thoughts on the GPRS/GSM features.** UPDATE **Due to OS updates, this HAT no longer appears to work at all now!Looking around on the usual forums, *no-one* seems to be able to get this HAT working, including Waveshare (their supplied scripts don't work). Move on, look elsewhere.

Hard to program