Potentially dumb question alert
Does anyone have any ballpark figures for how quickly an ardusimple board working on a base / rover setup updates the GPS?
I’m looking at running a vehicle that travels at 1MPS or around 2.2MPH and want to track and record its position as accurately as possible. If (say) its position is being updated every 5 seconds, then am I right in thinking that the coordinates will be out by up to 5m?
Mine is 8Hz.
Have you ever [had any cause to] measure this? Are you really getting 8 updates per second?
Edit: 8 accurate updates / fixes per second?
VTG and GGA data can be seen running into AOG at speed and it’s set up for 125ms intervals in U-Centre. Why would that not be the case?
My u-blox F9P calculates an accurate position at 10 Hz. As a rover it could do it even faster but only when a subset of GNSS constellations are used. My base supports GPS and GLONASS which is why the FP9 also runs GPS and GLONASS only and could do faster than 10 Hz.
My Topcon AGI-4 runs at 10 Hz too.
Because I’ve worked in networks for 20 odd years and one thing I do know is that claimed throughout is not equal to real life throughput, usually not even close!
But this is all new to me so perhaps we have an exception. The ardusimple does appear to buck this trend.
Fantastic, thanks guys.
Your position would be bouncing all over the place if it was unstable. Especially standing still. If there were misses the screen would stutter as fixes were dropped from bad data. Ublox i believe can do 20 hz as well.
10 isn’t a stretch at all.
That was my initial problem with standard GPS; drift. Trying to follow an AB Line is lots of fun when your vehicle thinks it’s at x, then thinks it’s 5m to the east, then 2m to the north, etc.
What were you using before your F9P that was so inaccurate?
I first tested AOG with a £12 patch receiver that actually wasn’t bad at all.
If you’re an expert in networking could you answer this one for me please?
“ What were you using before your F9P that was so inaccurate?”
A £7 Ublox GPS USB device 
What internal IP is port 2101 forwarding to? Is it NATd correctly (is the firewall pointing at the correct LAN IP address? This is set to static, right?)
The casters ip. No firewall on caster.
NATd??
NAT is Network Address Translation, it deals with how a single public IP address can route traffic to multiple internal IPs.
On your router, have you set a firewall rule to permit port 2101 to the internal IP address (typically 192.168.1.x) of your caster?
Have you set a static IP address for the caster? Is the Allow rule on your firewall pointing to this?
I’ve posted on my topic linked above what I’ve already done. I think I’ve done that already.
Let’s check and take it up in that thread.
@MortenP which .ino file do you mean?
I’ve just done the firmware update of my Ardusimple rtk2b and loaded the Ortner config file according to Andreas’ instruction.
Now I get RKT fix at 8 hz but the gps refresh rate remains at 5 hz. I never got 8 hz there so far.
Here’s a screenshot. It’s just the 5 Hz that puzzle me because I read here it’s supposed to be 8 Hz. After the firmware update and with Andreas’ config loaded ( c_f9p_fw1.12_ortner_vtg gga_8hz.txt, GPS refresh rate is still 5 Hz.
Is that alright or do I have to change something in a certain .ino file?
You can set NMEA Hz in “data sources”
Great! Thank you for answering my beginner question. Should have gone for the low hanging fruits first…