Lpc2000

Thank you!

Richard

--- In lpc2000@yahoogroups.com, "philips_apps" <philips_apps@y...> 
wrote:
>
> For reference the posting we did on Dec 22
> ----
> 1) Am I right in assuming LPC2000 CRP is a software fence 
implemented
> in the supplied boot loader code?
> 
> Partially. It is a combination of Hardware and Software supplied in
> the bootloader code. Application running in micro has full access 
to
> the entire memory space.
> 
> 2) I am going to replace the Philips bootloader. I have figured out
> how to do it.
> 
> Replacing the Philips bootloader is not recommended. It hides the
> underlying hardware and allows Philips to use new flash 
technologies
> without impacting the end user. Philips Bootloader may reside in 
ROM
> or write/erase protected flash making replacement impossible. In
> LPC2101/2/3 the bootloader resides in on-chip ROM.
> 
> 3) How is Bootloader programmed for the first time?
> 
> Via JTAG on a tester. JTAG is accessible in virgin devices. Once
> bootloader is programmed and CRP is enabled the tester can't access
> the JTAG.
> 
> 4) CRP in devices with internal flash and external bus.
> 
> The bootloader prevents external boot if CRP is enabled. User
> Application residing in on-chip flash which needs to be protected
> should not execute code from external memory.
> 
> 5) Can bootloader write/erase itself?
> 
> No.
> 
> 6) Can bootloader get corrupted?
> 
> Very unlikely if IAP/ISP calls are used for flash programming.
> Very likely if Flash programming interface registers are directly
> accessed for flash programming.
> 
> 7) Can Philips comment if Quick-Pulse parallel programming can 
void 
> CRP?
> 
> First of all there is no Quick-Pulse parallel programming option 
for
> ARM based micros. We are sorry for not making clear what is meant 
by
> "Parallel Programming" for ARM based micros. Parallel programming 
for
> ARM based micros just means that the device can be mass programmed 
in
> a commercial programmer. Parallel programmers still use JTAG and/or
> ISP and go through the bootloader IAP routines to program the on-
chip
> flash. It does not matter how a part is programmed. If CRP is 
enabled
> it will remain enabled once the part is programmed. If CRP is 
enabled
> a parallel programmer can't access the flash unless it erases the
> whole flash. Same applies to the ISP utility and JTAG based 
> debuggers.
> 
> 8) Is CRP option available for 2104/05/06?
> 
> Not yet.
> 
> 9) Devices with external memory bus can be forced to boot from
> external memory?
> 
> ONLY if CRP is NOT enabled or NO internal flash present. Also see 
> (4).
> 
> 10) Can I tell client Philips has confirmed CRP is not voided by 
PP?
> 
> Yes. Also see (7).
> 
> 11) How do I reprogram a CRP enabled part?
> 
> Erase all user sectors in one go via ISP. You can reprogram it 
after 
> a
> power cycle.
> Please note that the protected code vanished and was not visible 
to a
> "spy" or "praying eyes".
> 
> --------
> 12) Can JTAG be or remain enabled through clocking the CPU slowly 
> and JTAG fast during the initial time window after reset where 
JTAG 
> is enabled?
> 
> No, the clock for JTAG and the CPU are syncronized on these 
devices. 
> There are not enough JTAG clocks to control the CPU before the 
JTAG 
> gets disabled by the bootloader software. 
> 
> 13) Can the bootloader update be performed when CRP is enabled?
> 
> No, the bootloader update uses commands like copy RAM to Flash 
which 
> is disabled when CRP is enabled. The message will be that there is 
> no communication possible. 
> 
> 
> Comment to Robert Adsets posting:
> It is correct that support efforts would be significantly higher 
> with published source code of the bootloader and let me add 
without 
> adding any benefits to you, our customers.
>