39
W&T PC cards for ISA bus systems
Subject to error and alteration
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.
Galvanic isolation
The two ports of the W&T serial module mainboard are galvani-
cally isolated from each other and with respect to the PC for an
isolation voltage of 1kV. The signals are insulated 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.
Mainboard for Serial Interface Modules, #13001
