ROBOTC and the VEXnet Joystick

[Carter12s]

Hi, i am teaching a class this summer to a group of junior high school students about robotics. For the class we purchased 6 new Vex robot starter kits with the cortex microcomputer and the vex-net joystick. I am brand new to vex robots and robotc but i am having a great experience with it. The problem i have now is that i cannot find the proper notation for accessing button presses in ROBOTC. This is the code i am using right now

task usercontrol()
{
// User control code here, inside the loop

while (true)
{
motor[Left1] = vexRT[Ch3];
motor[Right1] = vexRT[Ch2];
motor[Arm1] = vexRT[ ???];

}
}

what i would like to do is define the motor[Arm1] to run off of button presses. I cannot find a chart showing the correct vexRT channels for the new vexNet joystick. does anyone have these?