wrong NAV-PVT payoad size?

bolderflight / ublox

Arduino and CMake library for communicating with uBlox GPS receivers.

MIT License

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wrong NAV-PVT payoad size? #1

Closed thezenox closed 3 years ago

thezenox commented 6 years ago

I'm working with NEO 6 M Modules but protocol should be the same. Regarding to protocol documentation: https://www.u-blox.com/sites/default/files/products/documents/u-blox7-V14_ReceiverDescrProtSpec_%28GPS.G7-SW-12001%29_Public.pdf the NAV-PVT has a payload of 84 bytes. Checksum is calculated over CLASS, ID, lenght and payload (in total 1+1+2+84 =88 bytes) but UBLOX.h says static const uint8_t _payloadSize = 96; for me it is only working with 88 bytes payloadSize, otherwise checksum fails

dollop80 commented 5 years ago

The UBX protocol for ublox8 gps receivers has payload size of 96 bytes and it is not backwards compatible with a protocol used by ublox6/7 gps receivers that has payload size of 88 bytes. So you are right, when using the library with receivers older than ublox8 it is needed to change the static const uint8_t _payloadSize = 96 to static const uint8_t _payloadSize = 88