NoAffinity
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I've spent the last week pulling my hair out over a set of CPS2 boards that would not reprogram with the encryption key (a.k.a desuicide). Thought I would share my findings. This is specific to rev -3 and rev -4 boards, those that use the CN2 connector to program the board. There have been a handful of reports of folks being unable to desuicide the rev -4 boards. I did not have this issue on a rev -7 board w/ CN9 connector.
Won't go into all the troubleshooting details. At the end of the day, the problem lay squarely with the power supply that I was using to power the Arduino. Below are the specs for the Arduino (source: https://www.arduino.cc/en/Main/arduinoBoardUno/).
Input Voltage (recommended) 7-12V
Input Voltage (limit) 6-20V
The board can operate on an external supply from 6 to 20 volts. If supplied with less than 7V, however, the 5V pin may supply less than five volts and the board may become unstable. If using more than 12V, the voltage regulator may overheat and damage the board. The recommended range is 7 to 12 volts.
Beyond that, what I've read is that the recommendations for current supply are 500mA - 1000mA. 1000mA is recommended when powering heavier loads through the Arduino, such as a motor or 20 LED's.
The power supply I was using initially is rated 7.5V @ 1000mA. I tested it with a multimeter, and found it to actually be putting out 12V. Should've still been within spec.
Today, I started grabbing any power supply I had in my possession that would physically plug into the Arduino. Started with a 9V 1.5A supply - should be good - the Arduino LCD screen wouldn't power properly.
I then grabbed a 5V 4A supply. It shouldn't be within spec, but this one ended up being the solution that finally worked and enabled me to revive/desuicide the boards.
So, if you're having problems desuiciding CPS2 boards that use the CN2 connector to program the board, try a 5V external power supply for your Arduino.
Won't go into all the troubleshooting details. At the end of the day, the problem lay squarely with the power supply that I was using to power the Arduino. Below are the specs for the Arduino (source: https://www.arduino.cc/en/Main/arduinoBoardUno/).
Input Voltage (recommended) 7-12V
Input Voltage (limit) 6-20V
The board can operate on an external supply from 6 to 20 volts. If supplied with less than 7V, however, the 5V pin may supply less than five volts and the board may become unstable. If using more than 12V, the voltage regulator may overheat and damage the board. The recommended range is 7 to 12 volts.
Beyond that, what I've read is that the recommendations for current supply are 500mA - 1000mA. 1000mA is recommended when powering heavier loads through the Arduino, such as a motor or 20 LED's.
The power supply I was using initially is rated 7.5V @ 1000mA. I tested it with a multimeter, and found it to actually be putting out 12V. Should've still been within spec.
Today, I started grabbing any power supply I had in my possession that would physically plug into the Arduino. Started with a 9V 1.5A supply - should be good - the Arduino LCD screen wouldn't power properly.
I then grabbed a 5V 4A supply. It shouldn't be within spec, but this one ended up being the solution that finally worked and enabled me to revive/desuicide the boards.
So, if you're having problems desuiciding CPS2 boards that use the CN2 connector to program the board, try a 5V external power supply for your Arduino.
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