rtd cpuModule CMC6686GX, Руководство пользователя

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Serial Port 2, P5 or CN8
The second serial port is implemented on connector
P5
or CN8
CN8
. It is normally configured as a
PC compatible full-duplex RS232 port, but you may use the Setup program to re-configure is as half-
or full-duplex RS422 or RS485. The I/O address and corresponding interrupt must also be selected
using Setup. The available I/O addresses and the corresponding interrupts are shown in the following
table
Second Serial Port UART
The second serial port is implemented with a 16550-compatible UART (Universal Asynchronous
Receiver/Transmitter). This UART is capable of baud rates up to 115.2 kbaud in 16450 and 16550A
compatible mode and 1.5 Mbaud in Enhanced UART mode, and includes a 16-byte FIFO. Please
refer to any standard PC-AT hardware reference for the register map of the UART.
RS232 Serial Port (Default)
The full-duplex RS232 mode is the default setting on the cpuModule. With this mode enabled, con-
nector
P5 or CN8 must be connected to RS232 compatible devices. The following table gives the
connector pinout and shows how to connect to an external serial connector, either XT (DB25) or
AT(DB9) compatible.
Facing
P5
or CN8
CN8
’s connector pins, the pinout is:
The following table gives the pinout of connector P5 or CN8CN8 when RS232 mode is enabled.
Second Serial Port Settings
I/O Address
Default IRQ
03F8H IRQ4
02F8H IRQ3
03E8H IRQ4
02E8H IRQ3
9 7 5 3 1
GND DTR TXD RXD DCD
GND RI CTS RTS DSR
10 8 6 4 2
Connector
P5 or CN8
in RS-232 Mode
Pin Signal Function in/out DB25
1 DCD Data Carrier Detect in 8
2 DSR Data Set Ready in 6
3 RXD Receive Data in 3
4 RTS Request To Send out 4
5 TXD Transmit data out 2
6 CTS Clear To Send in 5