title: Troubleshooting OPP
Archived 2026-09-13 from
https://github.com/missionpinball/mpf-docs/blob/main/docs/hardware/opp/troubleshooting.md.
Full raw markdown, as returned by the source fetch.
General troubleshooting guide first, then these OPP-specific steps:
mpf hardware scan shows whether OPP boards are talking to MPF over USB:
$ mpf hardware scan
Connected CPUs:
- Port: com1 at 115200 baud
-> Board: 0x20 Firmware: 0x10100
-> Board: 0x21 Firmware: 0x10100
Incand cards:
- CPU: com1 Board: 0x20 Card: 0 Numbers: [16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31]
Input cards:
- CPU: com1 Board: 0x20 Card: 0 Numbers: [0, 1, 2, 3, 8, 9, 10, 11, 12, 13, 14, 15]
- CPU: com1 Board: 0x21 Card: 1 Numbers: [0, 1, 2, 3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27]
Solenoid cards:
- CPU: com1 Board: 0x20 Card: 0 Numbers: [0, 1, 2, 3]
- CPU: com1 Board: 0x21 Card: 1 Numbers: [12, 13, 14, 15]
LEDs:
- CPU: com1 Board: 0x21 Card: 1
Add debug: true to the opp: config section for verbose diagnostics (slows MPF down a bit —
disable after debugging):
opp:
debug: true
If OPP boards can't answer polls fast enough, lower poll_hz (default 100):
opp:
ports: COM7
poll_hz: 50
Note: this increases time between switch reads — too low and you can miss hits between polls
(only do this if you're actually hitting issues).
(Points to the shared troubleshooting_coils.md/troubleshooting_lights.md/troubleshooting.md
snippets in mpf-docs — general driver/lighting troubleshooting steps, not OPP-specific content
beyond what's captured above.)