![4. Option Selection](/images/new-backgrounds/106009/10600917x1.webp)
FOUR PORT
4. Option Selection
NOTE
Be sure to set the address selections and jumper options before installation.
The board contains several jumper straps for each port which must be set for proper operation.
4.1 Port Enable/Disable
Each port on the Four Port
Headers
jumper must be on the IRQ4 setting. If COM2: is selected, this jumper must be on IRQ3.
NOTE
Most communications software applications default COM3: to IRQ4 and
COM4: to IRQ3. This requires the sharing of interrupts between COM1:
and COM3:, and between COM2: and COM4:. While this is the default, it is not always the best setting. Check your software configuration instructions to determine the most appropriate IRQ setting.
6