Adlink CoreModule 745 Manual do Utilizador descarregar pdf (Página 29)

Chapter 3 Hardware

CoreModule 745 Reference Manual 23

Serial Interfaces

The CoreModule 745 provides three serial ports: two RS-232/485/422 ports (COM1 and COM2) and one

RS-232 port (COM3). The SCH3114I-NU SIO contains the circuitry for all three serial ports and delivers

the signals through three transceivers. The two RS-232/485/422 ports require two transceivers: one

ADM213EARSZ (U11) for RS-232 signals and one LTC1334CG (U12) for RS-485/422 signals. The third

serial port requires only one ADM213EARSZ transceiver (U38) for RS-232 signals. The serial ports support

the following features:

• Three individual high-speed NS16C550A-compatible UARTs

• Programmable word length, stop bits and parity

• 16-bit programmable baud rate generator

• Interrupt generator

• Loop-back mode

• Three individual 16-bit FIFOs

• Serial Port Headers



J3 - Serial Port 1 (COM1) supports RS-232/RS-485/RS-422 and full modem support



J4 - Serial Port 2 (COM2) supports RS-232/RS-485/RS-422 and full modem support



J5 - Serial Port 3 (COM3) supports RS-232 and full modem support

To implement the two-wire RS-485 mode on any serial port, you must tie together the equivalent pins for

each port.

For example, on Serial Port 1, tie pin 3 to 5 and pin 4 to 6 at the J3 header as shown in Figure 3-1. As an

alternate, tie pin 2 to 3 and pin 7 to 8 at the DB9 serial connector for Serial Port 1 as shown in Figure 3-1.

Refer also to the following tables for the specific pin signals on each connector.

Figure 3-1. RS485 Serial Port Implementation

NOTE The RS-485/RS-422 mode can be selected for the COM1 and COM2 serial ports

in BIOS Setup under the Advanced>Super IO Configuration menu. However,

the RS-232 mode is the default selection (Standard) for any serial port.

NOTE The RS-422 mode uses a four-wire interface and does not require any pins tied

together, but you must select RS-485 in BIOS Setup and make sure the

termination jumper is removed.

CM745RS485jump_b

6810

Serial Ports

COM1 and COM2

(J3 and J4)

Standard DB9 Serial

Port Connector (Female)

Rear View

1 2 ... 24 25 26 27 28 29 30 31 32 33 34 ... 55 56

Sem comentários

Adlink CoreModule 745 Manual do Utilizador Página 29