I was an happy man until tomorrow morning
My happiness of using all of the 32K of flash memory (see my post here) has completely flatted down after I discovered that, after turning the power ON, my pro mini simply doesn’t start like it was doing yesterday. And I touched nothing! :o
Here what is happening: after uploading a sketch with the USBasp programmer the pro mini reset and start the program normally. If I turn it off and on again, it re-starts without problems.
BUT, if I
- turn off the pro mini,
- wait 1 minute,
- turn on the pro mini again.
then… nothings happens. The uploaded sketch simply doesn’t start… :o
If I turn it off/on in a range of max 20 seconds then no problems, if I wait too much before turning it on then I’m done. It doesn’t restart.
I have to upload again the same sketch to see arduino starting and working. What’s going on?
(In the attachment my simple circuit)
I thought that maybe the Vcc was going down for some strange reason, so I have attached my multi-meter to check it.
The voltage is 3.3-3.35 V, perfect for my ProMini 8Mhz/3v3.
I’ve also discovered one thing: after switching off the power, the voltage goes slowly down (like a discharging capacitor).
If I turn on arduino before it goes below around 0.10 Volt then it starts normally. On the other side, if the voltage drops below that value then arduino doesn’t restart when I switch the power on again.
If I replace my arduino on the breadboard with another one programmed by using a traditional FTDI breakout (max 30K of flash) then zero problem. I can power it off and on as many times as I want, zero problems.
So the problem must be the ISP programming itself.
What’s going on? Any idea? :-\
P.S: the arduino I’m using is new, never used before. By Sparkfun.