Rockwell Automation 57C570 AutoMax PC3000 User Manual User Manual
Page 131

11Ć3
Note: If you do not enable bit 15 (hardware handshaking) in the
SETUP parameter of the OPEN statement, only pins 2, 3, and 5 of the
port you OPEN are functional.
Pin Number I/O
RSĆ232 Function
2
I
Received data
3
O
Transmitted data
4
O
Receiver status
The signal is true whenever the receiver can
accept characters, i.e., when the receiver buffer
is not full. When the receiver buffer fills to within
53 characters, the signal is turned off. The signal
can be used to disable another transmitter. It
applies when hardware handshaking is enabled.
5
ground Signal ground
6
I
Receiver enabled
This signal must be true for the receiver to
accept characters. If the signal becomes false
while a message is being received, characters
being received are deleted and an error is
reported to the application software. This signal
applies when hardware handshaking is enabled.
7
O
Transmitter status
The signal is true whenever the transmitter is
sending characters. It is used to bracket" a
character transmission. It can be used to
enable/disable any type of external equipment,
such as a triĆstate transmit modem, which
requires an enable signal to output characters.
Refer to the OPEN statement in the BASIC
Language instruction manual for details about
the operation of the Modem Enable signal
(RTS).
8
I
Transmitter enable
The signal must be true for the transmitter to
send a character. This signal is typically used for
hardware flow control when hardware
handshaking has been enabled.
Use the following table to help you make the cable you need.
ББББББББББББББ
For an example of this cable configuration:
БББББББ
See:
ББББББББББББББ
ББББББББББББББ
modem transmit enable with no flow control
БББББББ
БББББББ
Figure 11.2
ББББББББББББББ
ББББББББББББББ
cable break detect
БББББББ
БББББББ
Figure 11.3
ББББББББББББББ
ББББББББББББББ
oneĆdirectional flow control
БББББББ
БББББББ
Figure 11.4
ББББББББББББББ
ББББББББББББББ
biĆdirectional flow control
БББББББ
БББББББ
Figure 11.5
ББББББББББББББ
ББББББББББББББ
RSĆ422 cable
БББББББ
БББББББ
Figure 11.6