A 3-bit DIP switch is three tiny manual ON/OFF switches in one package. Together they produce a binary number from 0 to 7, allowing selection of one of eight stereo channel pairs:
Table
Switch code
Selected Ultranet pair
000
Channels 1–2
001
Channels 3–4
010
Channels 5–6
011
Channels 7–8
100
Channels 9–10
101
Channels 11–12
110
Channels 13–14
111
Channels 15–16
Each switch would connect to a PLD input. Pull-up resistors provide a stable default logic level; closing a switch pulls that input low. The PLD reads the three-bit value and extracts the chosen pair from the decoded Ultranet stream, then sends those two channels to the ADAU1452 and PCM1795.
Current status: I have only explained and planned this circuit. Despite the earlier progress messages, I have not actually added components or wiring. Your current project access is comment-only, so I cannot modify this owner’s schematic. The project owner must grant edit permission—or you can duplicate the project into your own workspace—before I can implement and verify it.