Comfunc |
value (TRUE
<> 0, FALSE = 0) |
BAUD |
Port Baud Rate (9600,
14400, 19200, etc). |
BREAK |
TRUE/FALSE Break is asserted.
Break is generally used to "get the attention" of the connected
modem, terminal or system. |
BYTE |
Number of bits per byte
(4, 5, 6, 7, or 8). |
CD |
TRUE/FALSE Carrier Detect
state; synonym for RLSD (READ-ONLY). When CD is TRUE, the
DCE (modem) has a suitable connection on the communications channel present.
When CD is FALSE, there is no suitable connection. |
CTS |
TRUE/FALSE Clear-To-Send
state is returned (READ-ONLY). |
CTSFLOW |
TRUE/FALSE Enable CTS
output flow control (Input signal). When CTSFLOW is enabled, it
causes the DTE (computer) to stop sending data whenever the CTS signal
is set to logic low by the DCE (modem). Transmission continues when
the DCE (modem) sets the CTS signal back to logic high. The CTS
signal is usually used in response to an RTS signal. |
DSR |
TRUE/FALSE Data-Set-Ready
state is returned (READ-ONLY). |
DSRFLOW |
TRUE/FALSE Enable DSR
output flow control (Input signal). When DSRFLOW is enabled, it
causes the DTE (computer) to stop sending data whenever the DSR signal
is set to logic low by the DCE (modem). Transmission is enabled
when the DSR signal returns to logic high. The DSR signal is often
used in conjunction with CTS in response to a RTS signal. |
DSRSENS |
TRUE/FALSE Enable DSR
sensitivity. When DSRSENS is enabled, data received by the DTE (computer)
is placed into the receive buffer only if DSR is set to logic high.
If DSR is set low, received data is discarded. Enabling DSRSENS
allows DSR to enable or disable the DTE (the computer) to receive data
from the DTE (the modem). DSRSENS is rarely used in practical communications
situations. |
DTRFLOW |
TRUE/FALSE Enable DTR
handshaking flow control (Output signal). When DTRFLOW is enabled,
it signals that the DCE (modem) should prepare to connect to the communications
channel. DTR is usually used for modem on-hook/off-hook control,
but can also be used in conjunction with DSR for handshaking. |
DTRLINE |
TRUE/FALSE Enable DTR
line. When enabled, DTRLINE leaves the DTR line active when the
port is closed by the DTE (computer). This ensures that the DCE
(modem) does not close the communications channel when the port is closed. |
NULL |
TRUE/FALSE Null ($NUL)
bytes are discarded when read. |
PARITY |
TRUE/FALSE Enable parity
checking. This mode must be enabled for the other Parity options to be
selected. |
PARITYCHAR |
Character to use for parity
error replacement. PARITY must be enabled. |
PARITYREPL |
TRUE/FALSE Enable character
replacement on parity error. PARITY must be enabled. |
PARITYTYPE |
0 = None, 1 = Odd, 2 =
Even, 3 = Mark, 4 = Space. PARITY must be enabled. Default
= 0. |
RING |
TRUE/FALSE Ring indicator
is on (READ-ONLY). When RING returns TRUE, a ringing signal
is being received on the communications channel (by the modem).
RING approximates the state of the ringing signal; however, it may not
be reported accurately on all Windows platforms. |
RLSD |
Receive-line-signal-detect
(READ-ONLY). See CD/Carrier Detect above. |
RTSFLOW |
Ready To Send (Output
signal). 0 = Disable, 1 = Enable, 2 = Handshake, 3 = Toggle.
Toggle is used for half-duplex (2-wire) operations to "reverse"
the line. While the DTE (computer) is busy sending data, it raises
the RTS signal and the DCE (modem) blocks its data receive channel.
When RTS signal reverts to logic low, the DCE (modem) reverts to transmit
mode and the DTE (computer) switches to receive mode.
Handshake
mode causes the DTE (computer) to check the receive buffer (RXQUE) after
each character is placed into the buffer. When the buffer is 5/6th
full, the RTS signal is dropped. When the receive buffer drops to
below 1/6th full, RTS is raised again |
RXBUFFER |
Size of the receive buffer
in bytes. |
RXQUE |
Characters currently in
the receive buffer (READ-ONLY). |
STOP |
0 = 1 stop bits, 1 = 1.5
stop bits, 2 = 2 stop bits. |
TXBUFFER |
Size of the transmit buffer
in bytes. In some cases, Windows may not be able to report the transmit
size. |
TXQUE |
Characters currently in
the transmit buffer (READ-ONLY). |
XINPFLOW |
TRUE/FALSE Enable XON/XOFF
input flow control. When the DTE (computer) receive buffer is full,
an XOFF character is sent to the DCE (modem) to instruct it to halt transmission.
When the DCE is ready to resume transmission, an XON character is sent
to the DCE. Typically, XOFF is sent when the receive buffer has
less than 1/16th remaining, and XON is sent when the receive buffer drops
to less than 1/16th of its maximum size. Default = FALSE. |
XOUTFLOW |
TRUE/FALSE Enable XON/XOFF
out flow control. When enabled, the DCE (modem) sends an XOFF to
the DTE (computer) to halt data transmission to the DCE. When the
DCE is ready to receive more data, an XON character is sent. XOUTFLOW
typically uses the same 1/16th rules as XINPFLOW. Default = FALSE. |