rtd CMV6486DX100HR, User Manual

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34
Second Serial Port, CN8
The second serial port is implemented on connector CN8. It is normally configured as a PC compat-
ible 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, and includes 16-byte
FIFOs on both receive and transmit. Please refer to any standard PC-AT hardware reference for the
register map of the 16550-type UART.
RS232 Serial Port (Default)
The full-duplex RS232 mode is the default setting on the cpuModule. With this mode enabled, con-
nector CN8 must be connected to RS232 compatible devices.
The following table gives the connector pinout and shows how to connect to an external serial con-
nector, either XT(DB25) or AT(DB 9) compatible.
Facing the connector pins, the pinout is:
Second Serial Port Settings
I/O Address
Default IRQ Optional IRQs
02F8H IRQ4 IRQ3, IRQ5
02E8H IRQ3 IRQ4, IRQ5
Connector
CN8
: Pin Assignment in RS232 Mode
Pin Signal Function in/out DB25 DB9
1 DCD Data Carrier Detect in 8 1
2 DSR Data Set Ready in 6 6
3 RXD Receive Data in 3 2
4 RTS Request To Send out 4 7
5 TXD Transmit data out 2 3
6 CTS Clear To Send in 5 8
7 DTR Data Terminal Ready out 20 4
8 RI Ring Indicate in 22 9
9,10 GND Signal Ground -- 7 5
9 7 5 3 1
GND DTR TXD RXD DCD
GND RI CTS RTS DSR
10 8 6 4 2