Black Box RS-485 Manual De Usuario
7
CHAPTER 4: Option Selection
NOTE
Be sure to set the address selections and jumper options before
installation.
installation.
The board contains several jumper straps for each port which must be set for
proper operation.
proper operation.
4.1 Port Enable/Disable
Each port on the Dual Port RS-232/422/485 can be enabled or disabled with
switch position 8 on the DIP switch. The port is enabled with the switch ON
(or closed) and disabled when OFF (or open). If any port is disabled, be sure
to also disable the interrupt request for that port by removing the IRQ jumper
(see Figure 4-1).
switch position 8 on the DIP switch. The port is enabled with the switch ON
(or closed) and disabled when OFF (or open). If any port is disabled, be sure
to also disable the interrupt request for that port by removing the IRQ jumper
(see Figure 4-1).
I
NTERFACE
S
ELECTION
RS-422/485
To select the RS-422/485 mode of operation, install DIP shunts in sockets
found at E6 and E7. E6 sets Port 1 and E7 sets Port 2.
found at E6 and E7. E6 sets Port 1 and E7 sets Port 2.
RS-232
To select the RS-232 mode of operation, install DIP shunts in sockets found
at E5 and E8. E5 sets Port 1 and E8 sets Port 2.
at E5 and E8. E5 sets Port 1 and E8 sets Port 2.
IRQ Selection
Headers E1 and E2 select the interrupt request for each serial port (E1–Port
2, E2–Port 1). If COM1: is selected, this jumper must be on the IRQ4 setting.
If COM2: is selected, this jumper must be on IRQ3.
2, E2–Port 1). If COM1: is selected, this 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.
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.
4. Option Selection