Mesa 4I33, Руководство пользователя

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4I33 3
HARDWARE CONFIGURATION
PARALLEL PORT LOCATION
The optional on-card parallel port can be located at 4 different I/O addresses,
204H,208H,224H and 228H. These locations are determined by a PAL and can be
changed if needed. Jumpers W6 and W7 (labeled PLOC on card) set the parallel port
locations as follows:
W6 W7 LOCATION
DOWN DOWN 204H
DOWN UP 208H
UP DOWN 224H
UP UP 228H
SERIAL PORT INTERRUPT
The optional serial port can select from 8 interrupts. The interrupt is selected by
placing a jumper on one of the jumper locations from W8 through W15. These
jumpers are labeled with the IRQ number on the card. Interrupts are selected as
follows:
W8 W9 W10 W11
IRQ9 IRQ3 IRQ4 IRQ5
W12 W13 W14 W15
IRQ7 IRQ10 IRQ11 IRQ12
RS-485 RE OPTION
If the RS-485 option is installed, jumper W16 can be used to select whether the
RS485 receiver is enabled when transmitting. This can be useful for ‘collision
detection’ schemes. The disadvantage of having receive always enabled is that all
transmitted characters must be dumped from the receive buffer when done
transmitting.
When W16 is in the DOWN position, receive enable is always on. When W16 is
in the UP position, receive enable is off when transmitting.