Embedded Solutions
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BIS3_IO_RDBKUPR
[$C4] BiSerial III I/O Upper Read-Back Port read only
I/O Upper Read-Back Port
DATA BIT
DESCRIPTION
1-0
I/O Data 33-32
FIGURE 17
PMC BISERIAL-III I/O READBACK PORT
The I/O lines can be read at any time. The value is not filtered in any way. If the
transceivers are set to TX by the parallel port or state-machine then the read-back
value will be the transmitted value. If the transceivers are set to receive then the port
values will be those received by the transceivers from the external I/O. The upper bits
are presented on this port.
BIS3_STAT_FIFO
[$24] BiSerial III Switch Port read only
User Switch Port
DATA BIT
DESCRIPTION
31-24 Spare
23-16 sw7-0
15-0 Spare
FIGURE 18
PMC BISERIAL-III SWITCH PORT
The Switch Read Port has the user bits. The user bits are connected to the eight dip-
switch positions. The switches allow custom configurations to be defined by the user
and for the software to identify a particular board by its switch settings and to configure
it accordingly.
The Dip-switch is marked on the silk-screen with the positions of
the digits and the '1' and '0' definitions. The numbers are hex
coded. The example shown would produce 0x12 when read (and
shifted down).
