# cbTimerOutStart()

Starts a timer square wave output. Use cbTimerOutStop() to stop the output.

## Function Prototype

C/C++

int cbTimerOutStart(int BoardNum, int TimerNum, double *Frequency)

Visual Basic

Function cbTimerOutStart(ByVal BoardNum&, ByVal TimerNum&, Frequency#) As Long

## Arguments

BoardNum

The number associated with the board when it was installed with InstaCal or created with cbCreateDaqDevice(). BoardNum may be 0 to 99. The specified board must have a timer-type counter.

TimerNum

The timer to output the square wave from. Valid values are zero (0) up to the number of timers – 1 on the board.

Frequency

The desired square wave frequency. The timers clock will be divided down by integer values to produce the frequency. The actual frequency output will be returned. Valid values are dependant on the timer's clock and the timer resolution.

## Returns

- Error code or 0 if no errors
- Frequency – the actual frequency set.