Re: Detecting secondary controller (transmitter) in ROBOTC

VEX V5 Technical Support UNOFFICIAL Tech Support
#1

(Reposted from the ROBOTC Techincal Support Q&A forum)
https://vexforum.com/t/is-the-second-transmitter-connected/20853/1

You could try using vexRT[AccelXXmtr2], vexRT[AccelYXmtr2], or vexRT[AccelZXmtr2] to detect movement (or any value at all) from the secondary joystick to see if it’s connected.

#2

It also appears that in the RobotCIntrinsics.c file, located in the Includes Directory, there is an Enumeration, with these Intrincs, nVexRCReceiveState, opcdSourceSystem, kSystemVEXRCReceiveState.

If you Mask OFF the top 5 Bits, the result will be:
Zero for no Controllers
One for One Controller, or
Two for Two Controllers

I don’t know without compiling some Code, if One or All Three have the same Values…

This test requires no Inputs at all, from any of the Joysticks…




#elif defined(VEX2)

  typedef enum
  {
    vrNoXmiters           = 0,        // No transmitters connected
    vrXmit1               = 0x01,     //                          1 == Transmitter 1 connected
    vrXmit2               = 0x02,     //                          1 == Transmitter 2 connected
    vrBit2                = 0x04,     // Unused
    vrCompetitionSwitch   = 0x08,     // 0 == No Comp Switch      1 == Competition Switch attached.
    vrResetSlave          = 0x10,     // Unused
    vrGameController      = 0x20,     // 0 == Legacy75MHz,        1 == Game Controller
    vrAutonomousMode      = 0x40,     // 0 == Driver Control,     1 == Autonomous Mode
    vrDisabled            = 0x80,     // 0 == Enabled             1 == Disabled.
  } TVexReceiverState;
  intrinsic const TVexReceiverState variableIndex(nVexRCReceiveState,
opcdSourceSystem, kSystemVEXRCReceiveState);
#endif
#3

Yes, it’s very simple, just check the variable

nVexRCReceiveState

for example


if( nVexRCReceiveState & 0x01 )
    {
    // first joystick is connected
    }
if( nVexRCReceiveState & 0x02 )
    {
    // second joystick is connected
    }
#4

Hmm… There is a Conflict, seen here…

Some how I don’t think Everyone is on the Same Sheet of Music…

#5

I saw Jesse’s answer, however, I did test the variable with a partner joystick and it works as I described (under ROBOTC 3.04). You can also observe this under the system parameters debug window where the variable is also displayed.

#6