SH1107

[mikeysklar]

That is a long run to suddenly have a failure.

Since you are seeing a difference in behavior with the device ordering maybe you can carefully check each connector. I can see how a single cable or stemma connector being slightly loose would cause the display to blank.

[kenidowa]

I didn't realize your post until just now.
Although, I have used the same set of connectors and wire sets this whole time, they have been reconnected/reconfigured several times. I do not notice any loose connections. I will check further because I was suspicious of this early on.
I am now running a test with the latest configuration of ,devices before display, with the other SH1107 that I have. I have also run a test with the SSD1306 display with no failures and have use these displays on a number of projects with no blank display failures.
If it were a random connection problem, would there be a command that could be used to reset the display?
Currently, I believe it takes a restart of the program and possibly a power cycle.

[mikeysklar]

There is a Rst pin on the SH1107 display you can connect to a digital pin on your Pico.

adafruit_products_1_12_OLED_pinouts_RST.png (159.13 KiB) Viewed 68 times

[kenidowa]

After several long runs, some over 18000 cycles and more than 24 hrs. I am becoming convinced that it was some sort of connection problem. Possibly after making several rounds of connection setups it helped clean things up. It seems strange but the phantom seems to have gone away. Since, I had 2 SH1107's and they both exhibited the problem, perhaps the QWIIC connector used when they were built were slightly contaminated .
Anyway thanks for your thoughts on this.
Ken

[mikeysklar]

It look as though you have resolved the issue down to the connections not being stable enough.

As long as the STEMMA cables are from Adafruit, short and firmly connected that should be enough to avoid any sort of disconnect.

What did you have to do to establish a better physical connection?

[kenidowa]

I think the only thing that has improved/reduced failures is the use and multiple reconnections while investigating this issue. I suspect there was some contamination on the QWIIC connectors since both were bought at same time and likely came from same manufacturing cycle and over used wiped them clean. Of course making sure they are seated well is important but I have never had such a problem with other QWIIC connected devices. Other than the blank screen on the device there never was any error condition reported from the processor board.