Lpc2000

Hello Bruce,

On Tuesday 28 March 2006 03:04, Bruce Paterson wrote:
> Thanks for your reply Dominic.
> Some comments included below.
>
> Ah so the wiki refers to the SVN version !  That was the bit if
> information I was missing. Might be worth while mentioning in the wiki
> what version your instructions refer to, to avoid future confusion.
>
Thanks for the hint. I wanted to put that on every page, but forgot about it 
when I wrote the building page. Added.

> Now, before I spend some time getting doing my own windows based build
> on the latest SVN version (pain!), can you tell me whether there are any
> show stoppers in the mid-feb cygwin version(s) that will stop them
> working ? (ie could cause an erroneous "Error validating JTAG scan
> chain" error ?). I know it's always best to use the latest and greatest,
> but I also don't want to go barking up the wrong tree.
>
I've presented the mid-february version at the Embedded World (using the JTAG 
Accelerator) and it worked, so there should be no show-stopper.
Martin Thomas from WinARM has put a precompiled version on his page based on 
SVN revision 55 (current) - it's probably best to get this, if you don't want 
to build the OpenOCD yourself.

> I can put up with running from a cygwin shell for now. Perhaps mention
> this in the wiki till someone provides some better info.
>
I've put it into a new FAQ page: 
http://openfacts.berlios.de/index-en.phtml?title=OpenOCD_FAQ
It doesn't seem to be a generic problem though, as I believe some people are 
starting it from within Eclipse.

> I don't mind running with administrator privileges for now, so though
> giveio would be nice it's not my highest priority. Windows native also
> nice, but running from a cygwin shell is also not a huge burden. As long
> as the tutorial and/or wiki says that's what I need to do. (Documenting
> these particular issues is more important for me at this stage than
> fixing them).
>
I wish there were more people like you. I don't like windows, and ideally I 
wouldn't want to bother with native builds.
Well, people want it, and so I guess I'll work on this, but currently I feel a 
serious lack of motivation. Other things are a lot more fun to work on.

> I realised that. My chameleon.cfg file is not that file. I'll include
> the text of my one as I'm not sure attachments work on this list:
>
> ------------------------------------------
> #daemon configuration
> telnet_port 4444
> gdb_port 3333
> #daemon_startup reset <--- commented out for now as not in this version
>
> #interface
> interface amt_jtagaccel
> parport_port 0x378
> jtag_speed 4
> target arm7tdmi little reset_halt 0
>
>
> #jtag scan chain
> # format    L IRC  IRCM IDCODE (Length, IR Capture, IR Capture Mask,
> IDCODE)
> jtag_device 4 0x01 0xf 0x01
> ------------------------------------------
>
> I believe it matches what you said, but I'm not certain about the jtag
> scan chain.

The JTAG scan chain is fine, but you should add

reset_config trst_and_srst srst_pulls_trst

to have the OpenOCD initialize the reset lines and account for the 
(intentionally broken) reset handling on LPC2000 devices. There might be a 
bug in the OpenOCD that accidentially keeps reset asserted when no 
reset_config is specified - I'll check that.

You also have to change reset_halt in the target line to "run" (reset_run in 
current builds). Halting out of reset isn't possible on the LPC2000s (because 
of their reset handling).

Regards,

Dominic