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COM_INIT()
Initializes the port parameters
Syntax
COM_INIT(<nComPort>,[<nBaudRate>],[<cParity>],
[<nDataLength>],[<nStopBits>]) --> lInitialized
Arguments
<nComPort> Designates the port (1 to N) that is initialized.
<nBaudRate> Designates the selected baud rate for the port.
Settings of 300, 600, 1200, 2400, 4800, 9600 and 19200 baud are
possible. The default value is 300 baud.
<cParity> Designates parity in the following form: (E)ven, (O)dd,
(M)ark, (S)pace, or (N)one. The default value is (N)one.
<nDataLength> Designates the data length; seven or eight bits are
possible. The default value is eight bits.
<nStopBits> Designates the number of stop bits, one or two. The
default value is one stop bit.
Returns
If the com port is initialized successfully, the function returns .T..
Description
In order to use the serial port after you open it, four operating
parameters must have been passed to this function. These operating
parameters are the transmission speed (baud rate), the data length, the
parity, and the number of stop bits. Today most bulletin boards use the
configuration "300 - 9600 baud, 8N1". This configuration means eight
data bits, no parity, and one stop bit. What is important is that all
these parameters can be changed while the port is closed. Neither the
data buffer or the modem status register (DTR, etc.) are affected.
Notes
” The port must have been opened previously. It is impossible
to initialize a port prior to opening it.
” If any or all of the four operating parameters are not
designated, or are designated incorrectly, the standard arguments of
300 baud, no parity, eight data bits, and one stop bit is used.
Examples
” Open and initialize a port:
nBuff_size := 4000 // 4000 character buffer
lComOk := COM_OPEN(1, nBuff_size) // Open port
IF lComOk
* The port is open, now it is to be initialized with 1200
* baud, no parity, eight data bits, and one stop bit.
lInitOk := COM_INIT(1, 1200, "N", 8, 1)
IF .NOT. lInitOk
? "Port cannot be initialized !"
ENDIF
ENDIF
” You can also omit the last three parameters in the above
example because they correspond to the default settings:
lInitOk := COM_INIT(1, 1200) // Init. with 1200, N, 8, 1
See Also:
COM_OPEN()
COM_CLOSE()
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