Octagon XE-800, Справочное руководство

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Chapter 5: Serial ports
Description
The XE–800 SBC has two serial ports, COM1 and COM2, which are accessed for
RS-232C at the 20-pin connector at J15. For RS-422/485 use the 5-pin connector at
J5. These serial ports interface to a printer, terminal, or other serial device. Both
ports support 5–, 6–, 7–, or 8–bit word lengths, 1, 1.5, or 2 stop bits, and baud rates
up to 115.2K.
The serial ports have the following specifications:
16550 compatible
16-byte FIFO buffers
IEC 1000, level 3, ESD protection
— Contact discharge ±6 kV
— Air–gap discharge ±8 kV
Backdrive protection
Up to 115.2k baud operation
Mating receptacle
Use a VTC-20F or VTC-20M cable to connect the COM ports to external serial
equipment. The P2 and P3 connectors on these cables are DB-9 female (VTC-20F)
or DB-9 male (VTC-20M) connectors which plug directly into a 9-pin serial cable.
For RS-422 or RS-485 on COM2, use a 1.25 mm RS422/485 Cable (part #6393) and
connector J5.
Figure 5–1 (following page) shows two serial devices connected to the XE–800 SBC.
It also shows the schematic for connecting RS–422 and RS–485 devices. Note that
you cannot use COM2 for RS–232 and RS–422/485 at the same time.
Figure 5–2 shows a null modem adapter connected to the COM1 port of a VTC-20F.
A null modem adapter is required when connecting a serial console.
Serial port configurations
COM1 and COM2 are 8-wire RS–232 interfaces, using the 20-pin connector at J15.
COM2 can also be configured in BIOS Setup for 4-wire RS–422/RS–485 interfaces.
RS–422 and RS–485 use the J5 connector. Some configurations of RS–422/RS–485
also require termination jumpers.
The COM ports configurations are shown in table 5–1. Tables 5–2 and 5–3 show
the COM pin-outs for the two COM ports, and table 5–4 shows the jumper settings.
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