Lpc2000

--- In lpc2100@yahoogroups.com, "Paul Curtis" <plc@r...> wrote:
> 
> > -----Original Message-----
> > From: russian_beagle [mailto:russian_beagle@y...] 
> > Sent: 21 January 2004 20:30
> > To: lpc2100@yahoogroups.com
> > Subject: [lpc2100] Programming the flash memory through the JTAG port
> > 
> > 
> > Hi all!
> > 
> > Can I download my program into the FLASH memory using the JTAG 
> > port?  The CrossWorks utilize own loader from SRAM which program the 
> > FLASH segment using IAP. 
> 
> I don't believe that Philips publish anything that tells you how to
> program the flash on the LPC, other than by using the bootstrap loader
> or by calling a set of routines in the rom yourself (which the BSL
> itself uses).  As such, it is impossible to program the flash (read:
> nearly impossible) using pure JTAG.  Certainly, I believe Philips can
> change the flash controller or technology without changing the
> programming interface, so even if you did reverse engineer the bootstrap
> loader to figure out how to poke the flash controller, it's not
> guaranteed that the flash controller remains static across revs of the
> silicon, but the API will.
> 
> --
> Paul Curtis, Rowley Associates Ltd http://www.rowley.co.uk
> CrossWorks for MSP430 and ARM processors

It is "by definition" possible to program the device through JTAG.
However, Paul brought up the most important issue, compatibility over
a longer periode of time. If Philips does not publish the direct
programming sequence, they might have a good reason for it, one being
that changes can be made to the actual programming mechanism without
changing anything in the Programming Interface. 

I would HIGHLY recommend to use the internal routines provided by the
bootloader for ease of use as much as for avoiding future trouble in
case the mechanism actually changes. 

Being an embedded developer as well as involved with customer support
some times, I know that we all want to know HOW things work in detail
but sometimes it is time not well spent to dig into issues that can
only make live harder. 

On a side note, I don't try to figure out the exact procedures used by
the BIOS of my PC if I program something in Visual C++  :-)

Cheers, Bob.