Bitcraze Forums

Can someone explain what the Warnings and error messages from the Windows GUI software mean? For example I get, "No LogEntry to handle block=1; Error:cflig.crazyflie.toc:Got packet that was not on TOC channel, TOC fetch will probably not succeed....I also get lots of, Warning: Error! Older timer whas running while scheduling new one

Thanks

Hi,

This isn't as bad as it looks, but there's a issue reported for it and it should be fixed.

The first message Error:cflig.crazyflie.toc:Got packet that was not on TOC channel, TOC fetch will probably not succeed is a printout that's in place to help debugging the logging/parameter TOC that enables logging of data from the Crazyflie. To make a long story short the problem is that when you disconnect from the Crazyflie and then reconnect again logging data will be received when downloading the TOC and the client tries to decode this as TOC packets. This data is discarded but shows that there's a problem. The TOC download should still succeed.

The second message Warning: Error! Older timer whas running while scheduling new one has to do with the safe sending mechanism. When sending a packet to the Crazyflie from the PC you will get an ACK back from the radio verifying that the packet was received. This mechanism doesn't work the other way around, there's no ACK when sending data from the Crazyflie to the PC. So only the uplink is "safe" not the downlink from the Crazyflie. This means that if the client requests to get some information (like information about the TOC) the request will be ACKed, but there's no way for the Crazyflie to know if it has successfully sent pack the TOC data since there's no ACK from the PC to the Crazyflie. So there's some logic to keep asking for replies after a certain timeout. This is working, but it's far from optimal. The message indicates that a new request was made while waiting for the answer from a previous one.

The first thing that the client asks the Crazyflie for when connecting is the CRC of the TOC. It then tries to load the TOC from the local cache instead of downloading all of it from the Crazyflie. So even if the TOC downloading is slowed down by these errors it shouldn't be noticeable unless you are changing what variables are logged and what parameters are present.

Excellent. Thanks for the info