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Topic: reliable startup? (Read 3 times) previous topic - next topic

spencoid

i have done nothing in software to change the default behavior. pressing the restart button always fixes the problem and the program can run for hours with no problems. it is difficult to believe that no one else is having the problem.

on another annoying problem that i mentioned on another thread with no answers:
windows is an absolute horror in terms of connecting to serial ports. some times i need to erase restart unplug and replug the DUE several times and wait unknown periods of time before i can get a serial port (USB) connection. i have found but not tried some serial port utilities. any ideas on how to eliminate this? i spend more time plugging and unplugging and restarting and waiting for code to eventually not upload due to no serial connection than i do programming.

if i just knew what the rules were (wait a certain period or ???) i could handle it but having every connection a frustrating resetting replugging over and over is getting really old. could this be caused by the same problem as the powerup? is the computer not seeing the connected device properly? i do get the confirmation sound when i plug into the USB port.

brichs

I have experienced the same problem, and resetting the board always works for me. The best I've come up with is to throw on a Power-on reset IC to automate that process for me, but have yet to find the real hardware issue with this.

spencoid

do you have a recommendation for a real simple power on reset chip? does this look like the simplest solution?   texas instruments TLC7705 it will hold the reset line low until system voltage reaches 5 volts and the time delay (set by external cap) has expired. also has inverted reset output.

brichs

This is the chip I am looking into. It has a few different packages with varying threshold voltages:

http://www.ti.com/lit/ds/snvs003e/snvs003e.pdf

This is a relatively quick solution when the alternative is tearing out caps and resistors to reduce delays (which seems to be the issue as far as I can tell).

hiduino

Interestingly I have four Due boards and three different computer systems and have not had any USB connection problems.  They have worked reliably the first time I plug in.   There are exceptions I have been experiencing with the Due Native port not working with some USB cables.  But the Programming port has never had any problems.

It is sound like you may have some kind of hardware problem.  You need to narrow down the possibilities by replacing the USB cable, Computer, or Due board.  Which USB port on the Due have you been testing with?

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