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W&T
W W W . W u T . D E
Serial PC card
Module mainboard #13001
Function
The W&T serial module mainboard equip your PC with two independent serial interfaces with an insulation of up
to 1000 Volts. The integration of interface specific components in the form of exchangeable interface modules offer
the possibility of an optional card equipment with various types of interfaces. This makes it possible to concentrate
the connections of a RS232-COM1: for a mouse and a 20mA-COM2: for a control device on one card.
Both serial ports are equipped with type 16C550 FIFO UARTs; this makes them functionally compatible with
standard RS232 interfaces, so that the cards can easily be used with your available software. Following a reset, the
type 16550 elements are in standard UART operating mode, so that there is no need to worry about existing
software. The FIFO mode has to be activated explicitly by the software.
DMA operation of the 16550 UARTs is not supported by the hardware of the W&T port cards.
Insulation
The two ports of the W&T serial module mainboard are insulated both from each other and from the PC with a
dielectric strength of 1000 volts. The signals are isolated by means of high-speed opto-couplers; energy is supplied
to the driver and receiver elements by means of an isolated DC/DC converter.
Please note that the shielding of the
port connectors is directly connected to the case of the PC by the metallic back panel.
Configuring the card
The base address and the required interrupt line can be set by DIP switches at the lower edge of the card.
Port 2
interface module
socket
Port 1
interface module
socket
20V8
XT
AL
SW1
SW2
UART
Port 2
UART
Port 1
1
6
7
12
