Meilhaus Electronic ME-90 Series, Electronic Manual

Page: 43 / 120

3.5.5.2 Assignment of the PCI Slots
Because of the „stack architecture“ of PC/104-Plus the signals for
all extension boards are routed via one connector (in opposite to
the single slots of a motherboard). This means for the ME-90
PC/104-Plus, that the signals CLK, IDSEL and INT0# must be
routed to the PCI bus in a way that prevents conflicts with other
peripheral boards. The jumpers J1 and J2 control this (see Picture
29).
3.5.5.3 Configuration of RS-422/485 Ports
On the RS-422/485 models of the ME-90 PC/104-Plus series the
port configuration is done individually by the jumpers shown in
picture 31. The assignment to the single ports is shown in picture
28. You have the following configuration possibilities:
1.
Termination of the input and output buffer with the
resistors RT_IN and RT_OUT (default: 120
Ω
).
2.
Operation mode RS-485 half-duplex (see picture 50 on page
58). The connection between TxD+ and RxD+ as well as TxD-
and RxD- can be bridged easily by jumpers on the board.
3. Control of transmitter and receiver change-over
alternatively by the RTS (default) or DTR signal. Note that
one of both settings must always be plugged.
Echo ON/OFF see chapter 3.5.5.4 Echo ON/OFF, page 45