New revision o board pressure sensor values

[DaveK]

I recieved my new revision 'o' board from Unmanned Tech this weekend (very quick service). The board confused me a little while until I eventually found a page showing the 'o' revision hardware

Quick and easy to fire up using the FTDI lead and GluConfig 0.6. GPS data looking good but I'm having issues with some of the other sensor readings:

Pressure sensor is recording a pressure of 10331 Pa resulting in an altitude of 19880m. Temperature starts a little above room temperature but slowly climbs to upwards of 32ºC which is a little higher than the 19ºC it actually is indoors. I'm actually at sea level and the weather forecast is for a pressure of 1033.7hPa.

The board has the 0.7.0 software preloaded and was bought assembled and tested so I'm sure it is simply a case of me doing something wrong somewhere.

Dave

[Tom]

Hi Dave,

Thanks for your feedback.

The higher temperature is due to the processor heating up the board on your bench It's not an issue.

The low pressure is due to a small bug in your firmware. It doesn't affect the performance in the air, it's only the visualisation in gluonconfig that has this bug. Feel free to upgrade to a later version if you want.

Best regards,

Tom

[DaveK]

Many thanks. Temperature makes sense when I look at the board layout. I read the datasheet for the sensor and temperature not needed in their equations (temperature used for corrections at high altitudes?).

I used GluonCSInstaller_v0.7.2.exe. This installs the latest version of GluonConfig I would have thought.

Next question probably ought to go in Software but since I'm writing this post here goes:

If I run ds30LoaderConsole I get a console window briefly appear saying something about loading from database failed. The application then quits. Similar thing happens when using GluonConfig Firmware update button.

Dave

[Tom]

Apparently the devices.xml file is missing from the ds30 folder

Could you try with release 0.8beta? You can also use the firmware. It has been flight tested and is safe but still contains some small bugs.

[DaveK]

Sorted. Having messed about for a few hours I got it working. Using a laptop with Vista on it which I don't use often. When I manually downloaded GluonConfig and ran it from desktop it was fine.

GCS installed OK but doesn't run under admin which it needs to be. Today I saw the guide on the Unmanned Tech site which says just this.

Been reading the FreeRTOS book this evening so time to get serious

Many thanks for your help.

Dave

[DaveK]

I see that the temperature is used when calculating the pressure. Does the fact that it is approx 30+ degrees rather than the actual real temperature make any difference to the pressure and therefore altitude.

Dave

[Tom]

Pressure altitude is always relative, not absolute. This means that an offset in temperature (for example 10 degrees to warm) will have a small difference in altitude, but since the altitude is relative this doesn't really matter.