====== Put ======

''Put channel, data, byteLength''
| //channel// |RS-232 channel (1 to 3)   |
| //data// |Data to send (up to Long type value)   |
| //byteLength// | Length of data in bytes (1 to 4)   |

This command sends data on the specified RS-232 channel. For data,
variables and constants can be used. To send a String, please use the
PutStr command instead.

The OpenCom command must be used beforehand.

<code xbasic>
OpenCom 1,19200,0,50,10
Dim A As Byte
A = &HA0
Put 1,A,1    ' Send &HA0 (0xA0) to RS232 Channel 1.
</code>

The data is first stored in the send buffer set by OpenCom. The Cubloc
BASIC Interpreter will automatically keep transmitting the data until the
send buffer is empty.

If the send buffer is full when the Put command is executed, Put will
overwrite the data currently in the buffer. The BFree command can be used
to check the send buffer beforehand to prevent overwriting existing data in
the send buffer.

<code xbasic>
If BFree(1,1) > 2 Then    ' If send buffer has at least 2 bytes free
  Put 1,A,2
End If
</code>

Bfree is used to check how much free space the send buffer has before
writing any data to it.


==== TIP ====
After using Put or PutStr, the function Sys(0) can be used to verify that
the data has been stored in the send buffer.


<code xbasic>
OpenCom 1,19200,0,50,10
PutStr 1,"COMFILE"
Debug Dec Sys(0)   ' If output is 7, all data has been stored in the send buffer
</code>

Please refer to the On Recv interrupt service routine for receiving data
using the hardware serial buffer.



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