Instruction Manual

Card Setup

Sealevel Systems COMM+2/EX Page 3

Port Enable / Disable

Each port on the COMM+2/EX 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

disable the interrupt request for that port by removing the IRQ jumper.

Interface Selection

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.

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.

IRQ Selection

Headers E1 and E2 select the interrupt request for each serial port (E1 - Port 2, E2 - Port 1). If COM1: is selected,

the corresponding jumper must be on the IRQ4 setting. If COM2: is selected, the corresponding jumper must be on

IRQ3.

2/9 3 4 5 7 10 11 12 15

Figure 3 - Header E1 and E2, IRQ Selection

Any two or more ports can share a common IRQ, provided a polling driver is used, by placing the jumpers on the

same IRQ setting and setting the appropriate selections at E3. The following examples show the setup if a polling

driver is used. NOTE: Windows does not provide a polling driver. Consult your particular software for IRQ

selection. If no interrupt is desired, remove the jumper.