XTAL problem

cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

XTAL problem

643 Views
lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by GPh on Fri Nov 27 05:14:22 MST 2015
Hi,

I have a new LPC1758 board who don't work correctly with XTAL.
When i use internal oscillator is OK.
When i use XTAL is not OK. Debug probe don't connect each time, serial is not at the good speed, ...

When i use the same software on a LPC1768 board it's OK. (The design is the same on XTAL part)
I try many capacitor on xtal, same.
The XTAL is 16MHz same as on the other board ...

I don't know where is the problem and i don't know what i can look for resolve this.

If someone have some suggest ?

Thanks, Philippe.




Labels (1)
0 Kudos
5 Replies

585 Views
lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by  on Mon Nov 30 02:37:42 MST 2015
Is the problem that everything is correct? So far I  see nothing that may cause any troubles.
You may search some help at omniglot.com/language/articles/englishistricky.htm if needed.
0 Kudos

585 Views
lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by GPh on Mon Nov 30 02:29:04 MST 2015

Quote: R2D2

After telling us that your hardware is correct and your software is correct which kind of help are you searching  :~
Spiritual help?



Perhaps ...  0:)

I explain on my first post what i do.

The only change in my tests is the processor.
I only have one LPC1758 board, my other tests have been made with LPC1768.
Same desgin on the XTAL part, same regulator, same xtal.

LPC1758 & LPC1768 have the same core, only the number of pins change.
If the software work on 1768 i think it is good for the lpc1758. perhaps it's wrong ...
Can someone confirm ?

Thanks


0 Kudos

585 Views
lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by R2D2 on Fri Nov 27 08:09:45 MST 2015

Quote: GPh
The crystal frequency is good in software.
The crystal is running at really at 16MHz.
The hardware is OK.

I've done this checks and i find nothing wrong. It's why i'm searching help.  :)

I also check errata sheet.



:D

After telling us that your hardware is correct and your software is correct which kind of help are you searching  :~

Spiritual help?
0 Kudos

585 Views
lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by GPh on Fri Nov 27 07:40:25 MST 2015

The crystal frequency is good in software.
The crystal is running at really at 16MHz.
The hardware is OK.

I've done this checks and i find nothing wrong. It's why i'm searching help.  :)

I also check errata sheet.




0 Kudos

585 Views
lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by R2D2 on Fri Nov 27 07:13:15 MST 2015

Quote: GPh
If someone have some suggest ?



Debug your software and find out what's happening in detail...

Is your crystal setup for a 16MHz crystal?

Then check your hardware: look in the schematic and scope the crystal...
0 Kudos