Hi Simon,
thank you for your useful comment I used flashmagic and loaded a correct hex
file into the microcontroller and now all things are working good.
thanks for your helpful comment.
Hossein
--- On Tue, 5/4/11, simonb65 wrote:
From: simonb65
Subject: [lpc2000] Re: LPC2368 Wrong CCLKSEL value caused problems in
programming chip
To: l...
Date: Tuesday, 5 April, 2011, 8:09 PM
--- In l..., "Hossein" wrote:
>
> Hi all,
>
> I was working with my custom board which I designed
and recently I could write a simple firmware to turn off/on some LEDs, I wanted
to test what would happen if we program device with even values for CCLKSEL that
I saw it is not working any longer but when I changed the value to odd one and
tried to download the code to the chip I couldn't. I am working with H-JTAG
V0.4.3 and it gives an error message indicating that it couldn't halt the
cpu and take it in debug mode.
>
> does any one know how I can deal with this issue?
>
> thanks in advance.
>
You'll most likely find that the JTAG port is reliant on stable clock
settings. The only way I found round this is to flash a good firmware (sensible
clock values) using UART0 and the built in ISP using flash magic. Once you do
that, you'll find JTAG springs back to life again.
On 04/05/2011 02:41 PM, Hossein wrote: > I was working with my custom board which I designed
and recently I could
> write a simple firmware to turn off/on some LEDs, I wanted to test what
> would happen if we program device with even values for CCLKSEL that I
> saw it is not working any longer but when I changed the value to odd one
> and tried to download the code to the chip I couldn't. I am working
with
> H-JTAG V0.4.3 and it gives an error message indicating that it
couldn't
> halt the cpu and take it in debug mode.
>
> does any one know how I can deal with this issue?
As Simon said, you'll need a good clock for the JTAG. But it is enough
to reset the board into ISP mode and then you have internal 4MHz clock
and JTAG should be happy. Just be sure that JTAG clock is no faster than
(4/6)MHz (minus tolerances).
--
Timo
Reply by simonb65●April 5, 20112011-04-05
--- In l..., "Hossein" wrote: >
> Hi all,
>
> I was working with my custom board which I designed and recently I could write
a simple firmware to turn off/on some LEDs, I wanted to test what would happen
if we program device with even values for CCLKSEL that I saw it is not working
any longer but when I changed the value to odd one and tried to download the
code to the chip I couldn't. I am working with H-JTAG V0.4.3 and it gives
an error message indicating that it couldn't halt the cpu and take it in
debug mode.
>
> does any one know how I can deal with this issue?
>
> thanks in advance.
>
You'll most likely find that the JTAG port is reliant on stable clock
settings. The only way I found round this is to flash a good firmware (sensible
clock values) using UART0 and the built in ISP using flash magic. Once you do
that, you'll find JTAG springs back to life again.
Reply by Hossein●April 5, 20112011-04-05
Hi all,
I was working with my custom board which I designed and recently I could write a
simple firmware to turn off/on some LEDs, I wanted to test what would happen if
we program device with even values for CCLKSEL that I saw it is not working any
longer but when I changed the value to odd one and tried to download the code to
the chip I couldn't. I am working with H-JTAG V0.4.3 and it gives an error
message indicating that it couldn't halt the cpu and take it in debug mode.