====== FreqOut ======

''FreqOut channel, freqValue''
| //channel// |PWM channel (0 to 15)  |
| //freqValue// |Frequency value between 1 and 65535 |
 
FreqOut output the specified frequency to the specified PWM channel.
Please make sure to specify the PWM channel, not the I/O port number. For
the CB220 and CB280, ports 5, 6, and 7 correspond to PWM Channel 0, 1,
and 2, respectively.

The following chart shows several example freqValues and their
corresponding frequencies. The highest possible frequency can be achieved
by setting freqValue to 1 and the lowest possible can be achieved by
setting freqValue to 65535. A freqValue of 0 does not produce any
output.

^FreqValue ^Frequency^
|1 |1152 KHz|
|2 |768 kHz|
|3 |576 KHz|
|4 |460.8KHz|
|5 |384 KHz|
|10 |209.3 KHz|
|20 |109.7 KHz|
|30 |74.4 KHz|
|100 |22.83 KHz|
|200 |11.52 KHz|
|1000 |2.3 KHz|
|2000 |1.15 KHz|
|3000 |768 Hz|
|4000 |576 Hz|
|10000 |230 Hz|
|20000 |115.2 Hz|
|30000 |76.8 Hz|
|65535 |35.16 Hz|

You can calculate freqValue using the following formula:

freqValue = 2,304,000 / Desired Frequency

Before using this command, please set the specified PWM port to output
mode and set to a logic high or logic low state. To stop the output, use the
PWMOff command.

The following is an example: 

<code xbasic>
Const Device = CB280
Dim i As Integer
Low 5 ' Set Port 5 to low and output.
i = 1
FreqOut 0,10 ' Produce a 209.3Khz wave
Do ' Infinite loop
Loop
</code>

Since FreqOut uses the same resources as the PWM, there are some
restrictions to consider. PWM channels 0, 1, and 2 use the same timer. 

If PWM channel 0 is used for a FreqOut command, PWM channels 0, 1, and 2
cannot be used for a PWM command.

Likewise, PWM Channels 3, 4, and 5 are linked. If FreqOut is used on PWM
channel 3, PWM Channels 3, 4, and 5 cannot be used for a PWM command.

You can produce different frequencies on PWM channels 0 and 3.

To summarize, two different frequencies can be produced at one time, and
when using the FreqOut command, a PWM command cannot be used on the
same channel.

The following is a chart that correlates freqValue to musical notes:

^Note ^Octave 2 ^Octave 3 ^Octave 4 ^Octave 5^
|A |20945 |10473 |5236 |2618|
|B<sup>b</sup> |19770 |9885 |4942 |2471|
|B |18660 |9330 |4665 |2333|
|C |17613 |8806 |4403 |2202|
|D<sup>b</sup> |16624 |8312 |4156 |2078|
|D |15691 |7846 |3923 |1961|
|E<sup>b</sup> |14811 |7405 |3703 |1851|
|E |13979 |6990 |3495 |1747|
|F |13195 |6597 |3299 |1649|
|G<sup>b</sup> |12454 |6227 |3114 |1557|
|G |11755 |5878 |2939 |1469|
|A<sup>b</sup> |11095 |5548 |2774 |1387|

<code xbasic>
FreqOut 0,5236 ' Note A in Octave 4(440Hz)
FreqOut 0,1469 ' Note G in Octave 5
</code>

{{ :cubloc:freqout:freqout.png?nolink |}}

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