We have created 3 boards that utilize the Artemis and admit I am new to this and have lots to learn. We are developing in the Arduino IDE. One of the boards we have has been routinely been getting an error when uploading.
"Artemis SVL Bootloader
Target failed to enter bootload mode. Verify the right COM port is selected and that your board has the SVL bootloader."
This error comes after anywhere from 5 to 30 successful uploads on a fresh prototype board.
We have tried all the standard things like new cords, rebooting the computer, double checking the com port… and we can still program to other boards.
We have tried re burning the SVL bootloader per, https://github.com/sparkfun/Apollo3_Uploader_SVL the board would not accept a new bootloader
We have also manually pulled the boot pin high while attempting to upload as recommended by friend. no luck
We have slowed the upload speed to the slowest option. no luck
We are using a SparkFun CH340 Programmer. This most recent failure happened when power to the board was only provided by the CH340 programmer, 3.3v. We were using the serial monitor to verify the code being sent via BLE from our other board. The board that failed was freshly soldered today had 20-30 successful uploads and was working perfectly in all other aspects.
Our projects consist of 2 boards. Both are Artemis Powered. One consist of a 3.3v Buck converter with the recommended capacitors and resistors, a joystick and the Artemis Module. The Board that keeps failing uses the same 3.3v buck power circuit, 2 push buttons, and connectors to send data two 3 motor drivers, 2 are censored BLDC motors, and one motor is a small traditional brushed DC motor, each are on a separate power circuit. I thought that maybe we didn’t have appropriate capacitors on the leads of the brushed DC motor because 2 of the previous failures accrued while tuning the PID controller for that motor. But today the failure accrued with out that board ever being connected to a motor and as I said earlier it had only been connected to the CH340 during the failure.
The other odd thing to note is the program that was last uploaded still works per that upload and we can still get serial data from the Artemis through the serial monitor and CH340 but we cannot upload with out getting the SVL Bootloader error… this is true for every board that has failed. About 5 times. It now feels like Russian Roulette every time we upload.
In the end we have never revived a Artemis module once we get that error. We then resort to soldering together a new board . This has greatly slowed our development and we hope to resolve the issue.
Attached is the Ki CAD Files of the failing board. Sorry in advanced I am new to making boards so I hope everything is clear enough in the schematic.
Thanks