voytek

Hi,

We are kiosk manufacturer and are using your Netduino2 board as a general purpose controller in one of  products.

Its main purpose is to read some internal temperature sensors, control some PWM fans, read the fan speed, control a LED and a relay as well as some internal security switches.

We have designed our own custom shield to allow easy connection to our sensor and to condition the I/O signals such that they can work with the sensors.

We have built original batch of 25 units (about 2-3 months ago) without a single problem. They have been now deployed in the field and are working fine.

We have just started a build of further 150 units and have 14 faulty Netduino2 boards.

They all appeared to program OK (except perhaps one of them).

But once they are installed in the units they appear to be dead.

Once the boards are removed and inspected there seems to be a mixture of symptoms

Roughly half the boards only light up the white LED but not the blue LED, the other boards have both LEDs on.

Some boards emit buzzing sound (I assume it is the switching regulator experiencing excessive load)

All but one of the boards fail to connect to the PC in either boot loader mode or normal mode.

One board connects OK but the firmware download verify fails.

We would like your assistance in identifying the root cause of the problem, as you would have lot more experience with those boards.

Has anyone else reported similar problems ?

Is there a another method of resetting the CPU other than holding the button during power up sequence.

Any hints suggestions would be greatly appreciated.

Voytek