PCI 1 Port RS422/485
Software Setup
Chapter 3 Page 51
•
Receive Buffer - These settings allow the selection
of a receiver FIFO trigger setting. Selecting a low
value will allow the interrupt to be serviced quicker,
which is good for slow machines. If you have a fast
machine, setting a high value will give you more
time for multi-tasking operations.
•
Transmit Buffer - These settings allow the
selection of a transmitter FIFO trigger setting.
Selecting a low value will send fewer data-bytes per
interrupt, and this is recommended if you are
communicating to a slower machine. Selecting a
high value will send more data-bytes per interrupt,
and will give more time for multi-tasking
operations.
•
Use Extended FIFO Buffers - when checked,
extends the selected ports FIFO buffer from 16 to
64 bytes.
2. Automatic Hardware Flow Control. One of three
options may be selected:
•
Off (Default) - This will turn off automatic flow
control. (If you have no data transfer problems then
selecting this option is fine.)
•
RTS/CTS - This will use the RTS and CTS lines
for automatic hardware flow control.
3. 485 Mode offers the options:
•
Half Duplex / Full Duplex(default) - are used in
conjunction with the RS485 Multiplex Jumper
Settings.
NOTE: These software settings must match the
RS485 Multiplex Jumper configuration, as
described in the section "RS485 Multiplex Jumper
Settings" in Chapter 2, to ensure accurate and error
free data transmission.
