I'm having the same issue with a new PiCap. Display testing doesn't produce any results.
However, the fppd log
does show an error when the daemon is restarted.
Here's the relevant lines from the log:
2017-11-12 23:01:30 (3341) channeloutput/rpi_ws281x.cpp:220:ws2811_init() failed
2017-11-12 23:01:30 (3341) channeloutput/channeloutput.c:435:ERROR Opening RPIWS281X Channel Output
Pixels check good on an F4V3. Operation (or lack thereof) is the same on a Pi 2 and a Pi3. Tried FPP v1.8 and v1.9. No response with either.
The Cap is powered from a 12VDC suppy, pixels are 12V 2811s. String orientation confirmed via operation on the F4.
Both outputs read 12V when the Channel Output Testing Enable Test Mode box is checked.
Channel outputs screenshot attached.
String 2 behaves the same, i.e. no joy when it's configured for 50 pixels and String 1, zero pixels.
I've been an Electronics technician for 43 years, so I've tried to eliminate as many silly/stupid mistakes as possible, as well as pass along as much info regarding the configuration, and troubleshooting done so far.
Captain?
Can you go to the FPP Settings page and set your Log Level to Debug and make sure that at least the 'Channel Outputs' checkbox is checked for the Log Mask section, then restart fppd. Then go to the FPP File Manager and look at the tail end of the fppd.log file to see if there are any messages about the channel output. I'm running the latest stock v1.9 code on a Pi right now on an infinity mirror so I know the code should be working.