Q1: Where is the firmware of RAK2245+RPi?
Fomi: By now, there are two projects for RAK2245+RPi, one is based on LoRa Gateway OS, the other is based on Raspbian OS, both of them are fully open source. You can find them here:
Q2: How about the GPS function of RAK2245+RPi?
Fomi: RAK2245 integrates an Ublox MAX-7Q GPS module, and RPi connect to it through I2C . You can get the correct GPS data by using the above firmwares.
Q3: I can not get the GPS data and it returns some error like this: “[gps] read() returned value -1”, how can i fix this issue?
Fomi: Please try to reduce the I2C rate to 100K. (The default I2C rate of RPi is 400K)