If you have downloaded the b31 demo5 binaries from the rtkexplorer.com website before today, please download them again. The b31 source code is fine but I had a build issue caused by a combination of not doing a build from scratch and changes to the project file that I ported in from the 2.4.3 code. I know this can cause RTKCONV to crash for an illegal memory access. I don’t know if it can cause any other issues.
Sorry about that!
Also, I just added an update to the end of my previous post with some further analysis. It doesn’t change the overall conclusion, but it does impact some of the details, so you might want to re-read the post while you are downloading the new code.
rtklibexplorer 
RTKLIB Explorer,
Thanks for providing this resource to the community.
I am logging these messages to an SD card at 4hz.
(CFG-MSGOUT-UBX_RXM_RAWX_UART1)
(CFG-MSGOUT-UBX_RXM_SFRBX_UART1)
(CFG-MSGOUT-UBX_TIM_TM2_UART1)
(CFG-MSGOUT-UBX_NAV_POSLLH_UART1)
(CFG-MSGOUT-UBX_NAV_PVT_UART1)
When I bring the rov.ubx from the SD card into RTK plot , I don’t get any solution data. It doesn’t seem like the POSLLH message is being parsed out of the rover.ubx file.
Similarly, none of the events are being parse out.
I can see the events and position data from rov.ubx file when viewed in U-Center. So I know the data is in the rover.ubx file. Based on your blogs, I thought parsing the POSLLH and Events was automatic. Perhaps I am missing something in the RTKLIB configuration. I am using Demo 5 b31a.
Any help is greatly appreciated,
Dave
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Hi David. Sorry, mentioning POSLLH was a mistake on my part. Although I had the POSLLH messages enabled for other reasons in my experiment, I was actually using the $GNGGA NMEA message to collect the internal RTK engine solution. I have corrected this in the post. Thanks for catching this! Regarding the event logging, for the benefit of other readers, the reason it was not working for David is that RTKLIB only supports event logging for events in GPS time and he had configured the events to be logged in UTC time. See the details in the post for doing this with UBX-CFG-TP5 message.
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rtklibexplorer,
Thanks for the reply. Can RTKLIB extract position from the ublox PVT message? It doesn’t look like it. What’s the best way to extract real time internal position (rtk or stand alone ) from a ublox log file? Can this only be done via NMEA GGA.
Thank you,
David
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Hi David. Currently the only way to decode the u-blox position information from the u-blox receiver is with the NMEA GGA messages. You can improve the precision of the GGA messages using the UBX-CFG-NMEA config message as I mention in the post to match the precision of the other messages. Adding a function to ublox.c to decode the POSLLLH message would be fairly simple by using one of the other u-blox commmand decode functions as a template. The u-blox messages are well documented in the M8 Receiver document and the F9P Interface Description document, both available on the u-blox website.
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Thanks RTKExplorer. Based on my results (lack of) I assumed that was the case. We removed the POSLLH and added a precise GGA message to the logged file.
Another different but somewhat related question. If I am using RTK, is there anyway to extract events?
Thanks for taking the time to reply.
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Hi David. I don’t think I understand the question. If you save the raw binary messages from the receiver while processing a real-time (RTK) solution, the events will be logged, but the events themselves are an input to RTKLIB in real-time, so it doesn’t seem to make sense for them to also be a real-time output.
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rtklibexplorer,
Sorry my questions wasn’t clear. We are using the data logger to capture events to geotag images with high quality position data. Sometimes PPK is the only choice, other times RTK is a viable and preferred option. Either way we are logging the events to the sd card. I know we can extract the events if we go through the PPK process with RTKLib. However, I was wondering if there is a way to extract events without using RTKPOST from the sd card when the data was recorded using RTK. Running RTK quality data through RTKPOST would be redundant.
I understand events are realtime inputs but I am not writing positional data to an EXIF file in realtime. I am logging the events to use at a later time. As I think through my own answer, I just need to decode TM_TIM2 message.
Dave
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