Reply by cucu little July 3, 20062006-07-03
hi:
i meet a similar promblem in my designed board for lpc2103..
my suggest:
1):be sure oscillator is working, if using oscillation mode of operation ..take care of the value of external load capacitors..
2):you can use a philips isp tools to check if lpc210x alive..in this way it just need UART0.
good luck.


---------------------------------
ΧΆ3.5G20M







An Engineer's Guide to the LPC2100 Series

Reply by Sagaert Johan June 22, 20062006-06-22
hi

One thing to keep in mind

The capacitance of a scope probe could be enough to stop the oscillator when you try to measure in the xtal pins.
Use a low cap probe, or put an old axial resistor 100K on the probe tip to minimize the load.

Johan

----- Original Message -----
From: Danish Ali
To: l...
Sent: Wednesday, June 21, 2006 1:57 PM
Subject: [lpc2000] Re: still question ARM alive??? please help!
Sorry to be the bearer of bad news.

The DC voltages on the crystal pins are a bad sign.
You measure both 0V (as near as makes no odds).

If the inverter input X1 were low, X2 should be high.

They should be nominally half the core voltage.
This implies that the core (which should be 1.8V)
is actually at 0V.

I reckon either your power supply is not getting to
the LPC2104 or the LPC2104 is dead. (Or your voltage
measurements were wrong).

- Danish
--- In l..., omkar vyas wrote:
>
> hi Leon,
> i am using 15pf;with the crystal of 11.0592 Mhz!
> ya n as Danish have asked i am using X10 mode of oscilloscope probe.
> dc voltage level at pins X1 = - 0.009(minus) ,X2 = -0.004(minus).
>
> >>You imply this is your own board design. ya this is my first
design of microcontroller
> >> is the layout around the
> cystal very direct?
> -yes it is direct
> >> And have you connected all the supply and ground pins up?
> -yes i have
> >> And does every power pin
> have its own 0.1 uF decoupling capacitor within 5 mm
> of that pin and an equally direct ground connection?
> -yes but not all
> simple RC network is used for reset



Reply by Danish Ali June 21, 20062006-06-21
Sorry to be the bearer of bad news.

The DC voltages on the crystal pins are a bad sign.
You measure both 0V (as near as makes no odds).

If the inverter input X1 were low, X2 should be high.

They should be nominally half the core voltage.
This implies that the core (which should be 1.8V)
is actually at 0V.

I reckon either your power supply is not getting to
the LPC2104 or the LPC2104 is dead. (Or your voltage
measurements were wrong).

- Danish
--- In l..., omkar vyas wrote:
>
> hi Leon,
> i am using 15pf;with the crystal of 11.0592 Mhz!
> ya n as Danish have asked i am using X10 mode of oscilloscope probe.
> dc voltage level at pins X1 = - 0.009(minus) ,X2 = -0.004(minus).
>
> >>You imply this is your own board design. ya this is my first
design of microcontroller
> >> is the layout around the
> cystal very direct?
> -yes it is direct
> >> And have you connected all the supply and ground pins up?
> -yes i have
> >> And does every power pin
> have its own 0.1 uF decoupling capacitor within 5 mm
> of that pin and an equally direct ground connection?
> -yes but not all
> simple RC network is used for reset

Reply by "ian.scanlon" June 21, 20062006-06-21
--- In l..., omkar vyas
wrote:
>
> hi Leon,
> i am using 15pf;with the crystal of 11.0592 Mhz!
> ya n as Danish have asked i am using X10 mode of oscilloscope probe.
> dc voltage level at pins X1 = - 0.009(minus) ,X2 = -0.004(minus).
>
> >>You imply this is your own board design. ya this is my first
design of microcontroller
> >> is the layout around the
> cystal very direct?
> -yes it is direct
> >> And have you connected all the supply and ground pins up?
> -yes i have
> >> And does every power pin
> have its own 0.1 uF decoupling capacitor within 5 mm
> of that pin and an equally direct ground connection?
> -yes but not all
> simple RC network is used for reset
>
> Leon Heller wrote: -
---- Original Message -----
> From: "Julian Heller"
> To:
> Sent: Wednesday, June 21, 2006 7:58 AM
> Subject: Re: [lpc2000] still question ARM alive??? please help!
>
> > ----- Original Message -----
> > From: "omkar vyas"
> > To: "probs"
> > Sent: Wednesday, June 21, 2006 7:45 AM
> > Subject: [lpc2000] still question ARM alive??? please help!
> >
> >
> > as i have posted previously i have developed ARM lpc 2104 board
and its
> > not working
> > 1.now i have checked Flux i have cleaned it.
> > 2.i have checked all ground connections.
> > 3.crystal works fine if i connect some another module say 8051
it means
> > that my crystal is working but it is not working with ARM
> > 4.reset i have checked 10k resistance and 1 micro farad
tantalum
> > capacitor is i am using so it gets charged up by taking time of
> > 30milliseconds
> > 5.supply 1.8v and 3.3volts are working fine
> >
> > crystal is ok but as i use my ARM module with the crystal that
crystal
> > does not osculate...
> >
> > still ARM lpc 2104 is not working!
> >
> > Does ARM have any pin which says it is working or not?
> >
> >
> What value capacitors are you using with the crystal and what is
the
> frequency?
>
> Leon
>
>
>
>
>
>
> ---------------------------------
> Sneak preview the all-new Yahoo.com. It's not radically different.
Just radically better.
>
>
>
I feel your frustration.
I think it may be time to take a few steps back. In my experience,
the three most common problems when troubleshooting:
1) Power problems. Correct voltages on all of the right pins? Use a
meter to measure resistance from Supply/supplies directly to each
pin - not just the power pins, and really on the pin - not the pad.
Do the same for the ground.
2)Electro-mechanical failures. Bad solder joints, broken connectors,
sockets, relays, switches etc. Flex the board a bit or apply a bit of
pressure to the chip and watch the signals and the power.
3) Design / wiring problems. Check for two outputs driving each
other to opposite levels. Check this with a scope. Outputs (and
inputs too) should be very close to Vcc or GND.

You seem to be going the right direction looking at the oscillator,
but for every idea and observation make sure you can't attribute it
to something else first. You have been offered many excellent
debugging tips from many forum members and I think it might be best
to try them and get some more data first than keep guessing. Someone
(sorry, can't remember who) suggested trying a pull-up / pull-down on
the osc input to see what you get on the output. Also, can the output
be pulled up or down? you could do these test with the xtal in place
and get a good idea what specifally isn't working in the osc.
Someone else suggested driving the xtal input from an external
oscillator. That should give you some more info. Both xtal input
and output at 0V?? I would guess power problem too. You described
POR test. Is that directly on the reset input pin?

Last point - find what is wrong, then fix it.

good luck
Ian

Reply by leon_heller June 21, 20062006-06-21
--- In l..., omkar vyas
wrote:
>
> hi Leon,
> now i have changed crystal capacitors to the value 56pf still i
didn't get the crystal frequency oscillations! :-(
>
> now i have created two modules of ARM only but for module one i got
frequency at its X1, and x2. but i guess this processor is dead coz
accidentally one of us have given 4.22volts to the ARM core i think
this have damaged that ARM but now once again i have developed the
new board with proper components so now it is the case that i do not
get the freq at x1 and x2!!
> remaining all conditions are same as first module!
>
> two identical ARM lpc 2104 one is suffered from accident of 4.22
volts to core
> and other is not getting crystal frequency at x1 x2!
>
> which thing says that ARM is working?

Have you checked the spec. for the crystals you are using to make
sure that the ESR is in the correct range? That might make
oscillation marginal.

Leon

Reply by Leon Heller June 21, 20062006-06-21
----- Original Message -----
From: "omkar vyas"
To:
Sent: Wednesday, June 21, 2006 12:28 PM
Subject: Re: [lpc2000] still question ARM alive??? please help!
> hi Leon,
> now i have changed crystal capacitors to the value 56pf still i didn't get
> the crystal frequency oscillations! :-(
>
> now i have created two modules of ARM only but for module one i got
> frequency at its X1, and x2. but i guess this processor is dead coz
> accidentally one of us have given 4.22volts to the ARM core i think this
> have damaged that ARM but now once again i have developed the new board
> with proper components so now it is the case that i do not get the freq at
> x1 and x2!!
> remaining all conditions are same as first module!
>
> two identical ARM lpc 2104 one is suffered from accident of 4.22 volts to
> core
> and other is not getting crystal frequency at x1 x2!
>
> which thing says that ARM is working?

Until you get the crystal oscillating you can't really do anything at all.
Did you take anti-static precautions when assembling the board? I've never
had any oscillator problems with an LPC2104 or 6 on any of my boards.

Leon

Reply by Peter Jakacki June 21, 20062006-06-21
Have you held the cpu in reset while checking the oscillator? This is
very important if you are trying to check it as some software may be
shutting the oscillator down. With that in mind, have you even tried to
place the chip in bootload mode?
*Peter*

omkar vyas wrote:
> hi Leon,
> now i have changed crystal capacitors to the value 56pf still i didn't
> get the crystal frequency oscillations! :-(
>
> now i have created two modules of ARM only but for module one i got
> frequency at its X1, and x2. but i guess this processor is dead coz
> accidentally one of us have given 4.22volts to the ARM core i think this
> have damaged that ARM but now once again i have developed the new board
> with proper components so now it is the case that i do not get the freq
> at x1 and x2!!
> remaining all conditions are same as first module!
>
> two identical ARM lpc 2104 one is suffered from accident of 4.22 volts
> to core
> and other is not getting crystal frequency at x1 x2!
>
> which thing says that ARM is working?

Reply by omkar vyas June 21, 20062006-06-21
hi Leon,
now i have changed crystal capacitors to the value 56pf still i didn't get the crystal frequency oscillations! :-(

now i have created two modules of ARM only but for module one i got frequency at its X1, and x2. but i guess this processor is dead coz accidentally one of us have given 4.22volts to the ARM core i think this have damaged that ARM but now once again i have developed the new board with proper components so now it is the case that i do not get the freq at x1 and x2!!
remaining all conditions are same as first module!

two identical ARM lpc 2104 one is suffered from accident of 4.22 volts to core
and other is not getting crystal frequency at x1 x2!

which thing says that ARM is working?

thankx!

Leon Heller wrote: ----- Original Message -----
From: "omkar vyas"
To:
Sent: Wednesday, June 21, 2006 9:40 AM
Subject: [lpc2000] still question ARM alive??? please help!

> hi Leon,
> i am using 15pf;with the crystal of 11.0592 Mhz!

That might be the cause of your problem, a much larger value is required! I
use 56 pF with a 10 MHz crystal. There is a table with recommended values in
the documentation.

Leon

---------------------------------
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Get on board. You're invited to try the new Yahoo! Mail Beta.



Reply by Leon Heller June 21, 20062006-06-21
----- Original Message -----
From: "omkar vyas"
To:
Sent: Wednesday, June 21, 2006 9:40 AM
Subject: [lpc2000] still question ARM alive??? please help!
> hi Leon,
> i am using 15pf;with the crystal of 11.0592 Mhz!

That might be the cause of your problem, a much larger value is required! I
use 56 pF with a 10 MHz crystal. There is a table with recommended values in
the documentation.

Leon

Reply by omkar vyas June 21, 20062006-06-21
hi Leon,
i am using 15pf;with the crystal of 11.0592 Mhz!
ya n as Danish have asked i am using X10 mode of oscilloscope probe.
dc voltage level at pins X1 = - 0.009(minus) ,X2 = -0.004(minus).

>>You imply this is your own board design. ya this is my first design of microcontroller
>> is the layout around the
cystal very direct?
-yes it is direct
>> And have you connected all the supply and ground pins up?
-yes i have
>> And does every power pin
have its own 0.1 uF decoupling capacitor within 5 mm
of that pin and an equally direct ground connection?
-yes but not all
simple RC network is used for reset

Leon Heller wrote: ----- Original Message -----
From: "Julian Heller"
To:
Sent: Wednesday, June 21, 2006 7:58 AM
Subject: Re: [lpc2000] still question ARM alive??? please help!

> ----- Original Message -----
> From: "omkar vyas"
> To: "probs"
> Sent: Wednesday, June 21, 2006 7:45 AM
> Subject: [lpc2000] still question ARM alive??? please help!
>
>
> as i have posted previously i have developed ARM lpc 2104 board and its
> not working
> 1.now i have checked Flux i have cleaned it.
> 2.i have checked all ground connections.
> 3.crystal works fine if i connect some another module say 8051 it means
> that my crystal is working but it is not working with ARM
> 4.reset i have checked 10k resistance and 1 micro farad tantalum
> capacitor is i am using so it gets charged up by taking time of
> 30milliseconds
> 5.supply 1.8v and 3.3volts are working fine
>
> crystal is ok but as i use my ARM module with the crystal that crystal
> does not osculate...
>
> still ARM lpc 2104 is not working!
>
> Does ARM have any pin which says it is working or not?
>
>
What value capacitors are you using with the crystal and what is the
frequency?

Leon

---------------------------------
Sneak preview the all-new Yahoo.com. It's not radically different. Just radically better.