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W&T
W W W . W u T . D E
Function
The W&T PC card 13401 equip your PC with two independent 20mA serial interfaces with an insulation of up to
1000 Volts.
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 and ESD protection
The two ports of the W&T serial PC card 13401 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.
All interface signal lines of the PC card 13401 are protected against electrostatic discharge of up to 15 kV according
to IEC 801-2, level 4.
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
Port 1
20V8
SW1
SW2
UART
Port 2
UART
Port 1
XT
AL
PC card 2 x 20mA
#13401
