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  • 4634 Programmer
    replied
    Originally posted by FTC7172 View Post


    Out of curiosity, is the workaround still needed for the 5.0 (Skystone) version of the app? I've looked at the README/ChangeLog to see if this problem has been addressed but wasn't able to find any mentions of it.

    Thanks!

    Pm
    The workaround is no longer needed in v5.x https://github.com/FIRST-Tech-Challe...ster/README.md

    Leave a comment:


  • FTC7172
    replied
    Originally posted by Tom Eng View Post

    Yes, to the best of our knowledge yes, if you use the older phones as the Driver Stations you should not need the workaround.

    Also, thank you for the tip on the Wi-Fi Frequency Band. Perhaps by setting it to one band or the other it might resolve the issue! GREAT suggestion! We'll test this.

    Tom

    Out of curiosity, is the workaround still needed for the 5.0 (Skystone) version of the app? I've looked at the README/ChangeLog to see if this problem has been addressed but wasn't able to find any mentions of it.

    Thanks!

    Pm

    Leave a comment:


  • Alec
    replied
    Originally posted by Tom Eng View Post
    Alec,

    Do you only see that "Wi-Fi Frequency Band" option on the E4 phones? I do not see that setting on my E5 phone (which is also a dual-band phone).

    Tom
    I don't have an Moto E4 or G5. I have a Motorola Droid Turbo (XT1254) running Android 6.0.1 (i.e. non-FTC phone).

    The "Wi-Fi frequency band" setting on the Droid Turbo is located at [ Settings / Wi-Fi / ... / Advanced / Wi-Fi frequency band ].

    Leave a comment:


  • Tom Eng
    replied
    Alec,

    Do you only see that "Wi-Fi Frequency Band" option on the E4 phones? I do not see that setting on my E5 phone (which is also a dual-band phone).

    Tom

    Leave a comment:


  • Tom Eng
    replied
    Originally posted by Alec View Post
    Ok thanks... We have a several Motorola Moto G 2nd Gen phones. If we use the Moto G 2nd Gen phones for the DS and the Moto G5 or G5 Plus phones for the RC, the workaround is not needed. We won't be able use 5 GHz, but we will be able to use 2.4 GHz without the workaround. Is this correct?
    Hi Alex,

    Yes, to the best of our knowledge yes, if you use the older phones as the Driver Stations you should not need the workaround.

    Also, thank you for the tip on the Wi-Fi Frequency Band. Perhaps by setting it to one band or the other it might resolve the issue! GREAT suggestion! We'll test this.

    Tom

    Leave a comment:


  • Alec
    replied
    Also, if you change the Wi-Fi frequency band setting on the Moto G5 Driver Station phone to 5 GHz only (or 2.4 GHz only), would this resolve the issue?

    Leave a comment:


  • Alec
    replied
    Ok thanks... We have a several Motorola Moto G 2nd Gen phones. If we use the Moto G 2nd Gen phones for the DS and the Moto G5 or G5 Plus phones for the RC, the workaround is not needed. We won't be able use 5 GHz, but we will be able to use 2.4 GHz without the workaround. Is this correct?

    Leave a comment:


  • Tom Eng
    replied
    Hi Alec,

    The problem happens when the newer phones are used as a Driver Station (G5, G5 Plus, E4, E5). We think we know what the problem is caused by. The Motorola phones can scan the wireless spectrum (to detect what wireless resources are in the vicinity). We believe that when the system is in the WaitForStart mode, the Driver Station phone might decide to scan the spectrum if there is relatively low wireless activity happening.

    For the older Motorola phones (G4 Play, G 2nd gen and G 3rd gen) this scan completed in a short amount of time since the phone only scans the 2.4GHz channels. With the newer phones (E4, E5, G5, and G5 Plus), the scan physically takes more time because it also scans the 5GHz (non DFS) channels.This longer scan can cause the safety timeout mechanism of the FTC software to kick in (the wireless radio is being used by the scan process so it's not available for the FTC Driver Station app to send heartbeat messages to the Robot Controller).

    Sending the telemetry messages from the RC to the DS while waiting for the start seems to suppress this scan mechanism.

    We are working with some contacts at Motorola to try and find the optimal solution to our problem. For now, the workaround described in the link below is the best recommended course of action.

    https://github.com/ftctechnh/ftc_app...eported-102018

    Leave a comment:


  • Alec
    replied
    Thanks Tom, I will go ahead and seek a ruling on the legality of the Moto G5 Plus. Did you mean to say "If these phones are used as a Robot Controller" instead of "Driver Station":

    Originally posted by Tom Eng View Post
    Hi Folks - Note that this problem is not limited to the Motorola E4 phone. The same behavior occurs for the Moto G5 and G5 Plus phones. If these phones are used as a Driver Station...

    Leave a comment:


  • Tom Eng
    replied
    Originally posted by Alec View Post

    A phone cannot be legal unless the Tech Team has tested it. Your previous posts suggest that the Tech Team has tested the Moto G5 Plus. Please confirm that the Tech Team has tested this variant of the G5 so that we can have a basis for seeking a ruling from the Q&A forum.
    Hi Alec,

    Yes we have tested the G5 Plus phone.

    Tom

    Leave a comment:


  • Alec
    replied
    Originally posted by Tom Eng View Post
    ... Regarding the status of using a G5 Plus, I think the best place to ask the question is on the Q&A forum. I am unable to rule on its legality for use in FTC...
    A phone cannot be legal unless the Tech Team has tested it. Your previous posts suggest that the Tech Team has tested the Moto G5 Plus. Please confirm that the Tech Team has tested this variant of the G5 so that we can have a basis for seeking a ruling from the Q&A forum.

    Leave a comment:


  • Tom Eng
    replied
    Hi Folks - just some additional info...

    I believe the G5 Plus phone is very similar to the G5 phone, except it has a larger screen and a metal backing. Regarding the status of using a G5 phone, I think the best place to ask the question is on the Q&A forum. I am unable to rule on its legality for use in FTC.

    We have reached out to some contacts and have brought this issue to the attention of Motorola. I'll update the forum when we learn more about the issue.

    Tom

    Leave a comment:


  • 4634 Programmer
    replied
    Originally posted by Tom Eng View Post
    Thanks all for the detailed info. We'll check this out. I wonder if this is some type of power save issue (just thinking out loud - I do not have any evidence that it is).
    I think that's actually a very good hunch. My guess is that the radio is idling because of the low bandwidth usage. I've actually seen evidence of this on our Nexus 5s - when sitting idle the ping is ~25ms, but if I start moving around the analog sticks, it immediately drops to ~3ms

    Leave a comment:


  • Alec
    replied
    Originally posted by Tom Eng View Post
    ... The workaround prescribed for the E4 phone also works for the G5 or G5 Plus phones.
    Thanks Tom. Does this mean you heave tested and approved the Moto G5 Plus phone, i.e. it is now legal?

    Leave a comment:


  • Tom Eng
    replied
    Hi Folks - Note that this problem is not limited to the Motorola E4 phone. The same behavior occurs for the Moto G5 and G5 Plus phones. If these phones are used as a Driver Station and are in the waitForStart state for a period of time (which has been observed in as little as 30 seconds, or as long as 3 minutes) the Driver Station phone can disconnect momentarily from the Robot Controller.

    The workaround prescribed for the E4 phone also works for the G5 or G5 Plus phones.

    Leave a comment:

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