Omega Engineering OMG-COMM8-A Card Setup, Address Selection, Address Switch Position Setting

Card Setup

Card Setup

The OMG-COMM8-Acontains several jumper straps that must be set for proper operation.

Address Selection

The OMG-COMM8-Aoccupies 64 I/O locations and can be addressed two different ways. If header E1 is set to the “Switch” position the OMG- COMM8-Aoccupies 64 consecutive I/O locations and the DIP-switch is used to set the base address for these locations. The starting address for these 64 I/O locations must be on a 64-byte boundary i.e.: Hex 200, 240, 280, or 2C0. Be careful when selecting the base address as some selections conflict with existing PC ports. The following table shows several examples that usually do not cause a conflict.

Address

Switch Position Setting:

	1	2	3	4	5	6	7
100-13F	On	On	On	On	Off	On	On
180-1BF	On	On	On	On	Off	Off	On
240-27F	On	On	On	Off	On	On	Off
280-2BF	On	On	On	Off	On	Off	On
2C0-2FF	On	On	On	Off	On	Off	Off
300-3FF	On	On	On	Off	Off	On	On
500-53F	On	On	Off	On	Off	On	On
580-5BF	On	On	Off	On	Off	Off	On
1500-153F	Off	On	Off	On	Off	On	On
1580-15BF	Off	On	Off	On	Off	Off	On

Figure 1 - Address Selection Table

Note: Some of these selections may not be valid for your system, due to port contention. If in doubt, call Sealevel Technical Support

(864)843-4343 for assistance. These addressing restrictions are simplified when using the “PAL” option.

Note: If Xenix is the operating system and COM1 is not installed, use base address 500 Hex and IRQ 4 (Xenix COM1:). If COM1: is installed, then select 580 Hex as a base address and IRQ 3 (Xenix COM2:).

Omega Engineering OMG-COMM8-A Page 3