# cdiUserLed

Turns the application LED on or off.

#### Prototype

DWORD cdiUserLed ( CTAHD ctahd, DWORD value)

Argument | Description
ctahd | Context handle.
value | Value for the application LED. Refer to the Details section for more information.

#### Return values

Return value | Description
SUCCESS |
CTAERR_BAD_ARGUMENT | Argument is not in the valid range.
CTAERR_INVALID_CTAHD | Handle is invalid.

#### Details

CX 2000 boards have a green LED that the application can control. The application defines the purpose (generally maintenance, internal debugging, or other custom use). To control the LED, invoke cdiUserLed with one of the following values:

Value | Description
--- | ---
RESET_USER_LED | Turn off the application LED.
SET_USER_LED | Turn on the application LED
TOGGLE_USER_LED | Change the LED to the other state.