On the original DEVKIT-C (v1, I think), these switches never worked reliably. I got into the habit of holding down the boot button until flash started.
I just got a Geikcreit board (similar to DEVKIT-C) and that works well, including the SD CARD. But, I still get it jammed in 'waiting for download' after flashing (with IO2 and IO0 tied, and a 10K pull-up on IO2). A power on / off unplug cycle resolves that.
From what I can tell, we're on the fourth revision of auto-program transistor circuits.
- The first DEVKIT C used 1K resistors
- The second DEVKIT C used 1K resistors
- The third DEVKIT C uses 12K resistors
- The ROVER KIT adds a third transistor (to control IO2 independently) and 100K resistors
S8050 transistors look the same on all of these, as does the circuit schematic (except for the ROVER KIT addition of a third transistor).
Anybody know what is going on with this? What was the problem with the first DEVKIT C boards? What is the fix to make those work?
And, most importantly, what is the current recommended way of doing this?
Thanks, Mark.