I made a bunch of progress in the last 24 hours and can now send sketches to my ESP-12 modules via the Arduino IDE. The MEM CHECK FAIL message disappeared after uploading. It may be that there is a problem with the memory the sketches get stored in, but my little sketches are so small that they don't run across it, or it may have just been a bad image flashed to the module by the manufacturer.
On the one ESP-01 module I tried, I got the same message in its fresh-from-the-manufacturer state. So I'm thinking it was the manufacturer's image.
One of the ESP-12 modules is defective or was destroyed by myself. My guess is the latter.
kenn wrote:
I see that MEM CHECK FAIL message alot of the time... yet my uploaded program usually works... Maybe it means that the test itself is NFG...