Why my microcontroller hanging?

[MJDousti]

Hi,

I bought Atmel 89C51 (PC model) and I used it on my robot but after a
few second it stoped working.
What can I do?
BTW I have four high current (3A) relays on my circuit.
I added a bypass capacitor and shunt diode across the coiles of my
relays and and only one regulator for supply of microcontroller.
Also insert 2 capacitors (2200 uf, 10 uf) on the between GND and VCC.
Please help me?

 

[A E]

MJDousti wrote:

Hi,

I bought Atmel 89C51 (PC model) and I used it on my robot but after a
few second it stoped working.
What can I do?
BTW I have four high current (3A) relays on my circuit.
I added a bypass capacitor and shunt diode across the coiles of my
relays and and only one regulator for supply of microcontroller.
Also insert 2 capacitors (2200 uf, 10 uf) on the between GND and VCC.
Please help me?

You need the Macintosh model.

 

[MJDousti]

H again,
My problem is the noise of relays (I think).
So what is Macintosh model??

 

[Brett]

Couldn't it be bad software?

"MJDousti" <MJDousti@myrealbox.com> wrote in message
news:4e8f376f.0308080605.4eccdff0@posting.google.com...

H again,
My problem is the noise of relays (I think).
So what is Macintosh model??

 

[A E]

MJDousti wrote:

H again,
My problem is the noise of relays (I think).
So what is Macintosh model??

It was a joke.
Look, there's not much we can do over here without a lot more info. But here's
the three things I *always* check before checking anything else with
microcontrollers:
1) Power Supply. Check with a scope. Is it the correct voltage? Does it come up
fast enough to satisfy the chip's requirements? And when running, are there any
big spikes that might cause latch up? Any brownouts?
2) Reset circuit. This is simple, but often overlooked. The reset is usually a
RC network. Is it generating the correct polarity pulse for long enough? Use a
scope to check.
3) Oscillator. Again, this is simple, but often overlooked. Is the oscillator
starting up quickly enough? Is it at the correct frequency?

Once all these basic things are in place, then you start more serious debugging.

 

[R. Steve Walz]

Brett wrote:

Couldn't it be bad software?
----------

Won't eat the processor.
-Steve

"MJDousti" <MJDousti@myrealbox.com> wrote in message
news:4e8f376f.0308080605.4eccdff0@posting.google.com...
H again,
My problem is the noise of relays (I think).
-----------

No, the inductive kick of the relay coils.

So what is Macintosh model??
--------

Ignore him.

-Steve
--
-Steve Walz rstevew@armory.com ftp://ftp.armory.com/pub/user/rstevew
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