Product manual

Serial Solutions Range Product
Manual
© Copyright Brainboxes Limited 2010 Page 25 of 47
Some communications applications require the serial ports they access to be as named COM 4 or lower.
The COM port assignment may be changed, simply by selecting a new COM port value from the pull down
menu relevant to the port. However, COM port usage other than those for the selected card itself are not
checked, so it is advisable to first check which COM ports are in use – port availability can be checked by
viewing device manager.
All COM ports present will be listed under the entry “Ports (COM & LPT).”
Selecting the Maximum Baud Rate
The baud clock determines the maximum rate at which the serial ports of the PCI Multiport card can
communicate. The standard PC serial ports allow baud rates up to a maximum of 115,200; however, both
PCI Multiport cards can be set to use baud rates of up to 230,400 and beyond.
Double clicking a card entry under the “Multi-Function Adapters”, in Device Manager and select the Serial
Solutions tab. The maximum Baud Rate settings are located at the bottom of the Window.
The default Maximum Baud rate setting is 115,200 baud, which provides full backward compatibility with
standard serial ports. Any change to the baud rate settings here will affect all of the cards ports. Table 3-1,
below, lists the baud rates available at the various Maximum Baud Rate Settings. Setting the card to a
higher baud rate requires connection to a device that supports this higher baud rate. Whatever setting you
use will be stored by the PCI Multiport configuration software and set up again the next time Windows is
started. It has been found during testing that the PCI Quad / Lynx 8 Port RS232 will operates correctly up to
230,400 baud at distances of up to 10 metres.
Double clicking on a selected Multiport 232 Port entry in Device Manager will the display general properties
window for the selected port (in this case COM5)
Shared Interrupt Settings
Enable sharing – Clicking on this setting will remove the selected port from the shared interrupt, and will
require the particular port to be assigned its own unique IRQ value from the Resources Tab.
SISR address- This value is used in conjunction with the Enabling Sharing checkbox, and will appear
greyed out if the Enabling Sharing checkbox has been un-checked.
Port index – This is only used for interrupt sharing cards.
FIFO Settings
Enable FIFO – turns the selected ports FIFO buffer on or off. It is strongly recommended that the FIFO
for both ports is left enabled.
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 volume 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.
Restore
Clicking on this button will restore the port setting of the Serial Solutions tab for the selected port to:
Enable Sharing: On (Checked)
SISR Address: 3a0
Port Index: 0
Enable FIFO: On (Checked)
Receive Buffer: 3
rd
from right.
Transmit Buffer: High.