# Using Telemetry#

The SDK has “telemetry” that can be sent from the robot controller to the drivers station to display basic text. This telemetry is accessible through the Telemetry class, and the telemetry variable accessible in both OpMode and LinearOpMode.

## Building Telemetry#

There are two main methods used to add things to telemetry. addData() takes two parameters, a string for the caption, and then a value that can be any object. This is then printed on the phone screen in the format caption : value. These lines are keyed, so adding a secondary addData() with the same caption will override the value set.

telemetry.addData("Caption 1", 2.5);


The second method used to add things to telemetry is addLine(). Add line can be used to add a line with no parameters, or can take a single string to add as a line.

telemetry.addLine("This is a line!");


## Updating Telemetry#

Once all telemetry items have been added (typically at the end of an opmode loop), telemetry.update() must be called. Calling this method is what pushes the values to the phone, so without it telemetry will not appear on the phone screen. Note that OpMode will call telemetry.update() automatically once per call of its loop.

Tip

By default, telemetry is only refreshed on the phone every 250 ms. Any calls to telemetry.update() during this window will be saved and overwritten if update() is called again before 250 ms have elapsed. setMsTransmissionInterval() may be used to change the amount of time the SDK will wait between sending updates to the driver station.