dump code in lpc901 eeprom

Started by rudi, October 10, 2005, 06:45:18 AM

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rudi

hello together,

unfortunately I lost the source of a little remote control app for the lpc 901 by a hd crash. I only have a programmed chip. Is there any way to read the code ? If not, for what are the security bits good, at all ?

Thanks in advance

rudi

rudi

o.K.- no way also. now- I've the fourth segment of progmem free and gonna try to put a mini program there, that MOVCs the old prog and outputs it some way.
But how do I start the new prog ?
FlashMagic offers access to the bootvector in 901 ISP mode ( running prog90x.hex ) - does this mean the Bootvec/Statusbit in the 901 or the 935 on the MCB900 <;-] ??

rudi

Andy Ayre

ICP does not use the ISP bootloader, therefore there is no need for the boot vector or the status bit. They are only used when resetting the device into ISP mode.

Embedded Systems Academy, Inc.
support at esacademy dot com

rudi

Hello Andy,
the point is: instead of the original remotecontrolapp I want to read out on the 901 which has the entry point at 0x0000 I'd have to put the new MOVC-anykindof-output-loop in the 3rd segment at 0x0300 and of course start execution there.
Now I don't know, if the bootvec/Statusbit setting in flashmagic recognizes the prog90x.hex mode and sets the new entrypoint in the 901 instead of ruining another lpc935 on the mcb900  <8-(

regards
rudi

erikm

what you are saying (possibly for legit reasons) is "how do I stael the code in the chip?

What would be the purpose of security bits, readout disavble and who knows what to protect the code from theft, if there was a way to bypass it (possibly for legit reasons)?

Erik

rudi

Hello erik,
your suspicion lacks every rational reason. If you had properly read my posting your personal attacks would have been completely obsolete.

My appl is a simple multiplex switch for model aircraft purposes, with some practice one would write the code just before breakfast. But to evaluate the servo impulses there are a couple of timing parameters which took me s o m e  time to optimize, these are my cares. Then, in a irish-malt-inspirated night session I added a averageing error correction routine  
and ( of course ) didn't make any file backup ...
I hadn't any reason to set security bits, so they aren't set. It seems my question wasn't very good formulated ...

erikm

Hello erik,
your suspicion lacks every rational reason. If you had properly read my posting your personal attacks would have been completely obsolete.

(possibly for legit reasons)
hardly is a "personal attack"

Erik

helirudi

Finally found some time to get the code readout working. If someone's interested, here is the code

http://www.baedasui.de/downs/901.zip

There are two progs,

one for the 901, residing in the 0x300 segment ( sorry, a whole segment is to be cleared, so this one is lost forever ...) which outputs the content of the lower segs over a simple clocked serial protocol to the mcb900
and

one for the mcb itself which takes the stuff and sends it over the serial port to a pc.

Of course you have to set the boot vector of the ISPed lpc 901