Discussion forum for the BasicX family of microcontroller chips.
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It leaves the rest of EEPROM alone. I tried using the eeprom key idea ie place a PIN at the end of eeprom memory using one program The second program did not wipe the pin as it could compare a reference to it. I know Dan said it's bad to have a big empty space at the end of memory then the key, but what if we fill the eeprom with garbage first and have the key hidden somewhere in the middle of it (where the new program won't overwrite)? just a thought, Dave. Message: 12 Date: Sat, 27 Oct 2001 19:53:25 -0700 From: "Dan Bielecki" <> Subject: RE: RE: Software Download without BasicX downloader >> When you upload a new program to the BX, does it zero-out memory beyond the end of your >> program, or does it leave the rest of the EEPROM with whatever was there before? John? Wow! ..just never thought about it really until this thread. You really got something there.... Hummm...Im gonna go Peek and Poke around a bit...see what gets barfed out. .db. |
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It may get wiped out if there is a "Verify Error" or other problem with the download. I use the upper 7K or so of EEPROM for data storage and it sometimes gets corrupted if there's an error during the .bxb download. The higher in EEPROM, the less likely this will happen but I would not trust that even the highest EEPROM locations might not get corrupted on occasion. On 29 Oct 2001, at 16:18, David and Megan wrote: > It leaves the rest of EEPROM alone. > > I tried using the eeprom key idea > ie place a PIN at the end of eeprom memory using one program > > The second program did not wipe the pin as it could compare a > reference to it. > > I know Dan said it's bad to have a big empty space at the end of > memory then the key, but what if we fill the eeprom with garbage first > and have the key hidden somewhere in the middle of it (where the new > program won't overwrite)? > > just a thought, > > Dave. > Message: 12 > Date: Sat, 27 Oct 2001 19:53:25 -0700 > From: "Dan Bielecki" <> > Subject: RE: RE: Software Download without BasicX downloader > > >> When you upload a new program to the BX, does it zero-out memory > >> beyond > the end of your > >> program, or does it leave the rest of the EEPROM with whatever was > >> there > before? > > John? Wow! ..just never thought about it really until this thread. > You really got something there.... Hummm...Im gonna go Peek and Poke > around a bit...see what gets barfed out. > > .db. > ------------------------ Yahoo! Groups Sponsor > ---------------------~--> Pinpoint the right security solution for > your company- Learn how to add 128- bit encryption and to authenticate > your web site with VeriSign's FREE guide! > http://us.click.yahoo.com/yQix2C/33_CAA/yigFAA/CFFolB/TM > ---------------------------------------------------------------------~ > - > > --- http://www.laser.com/dhouston/ |
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A check box on the chip preference window would be a nice feature for that...Clear eeprom prior to download / Dont clear eeprom. Id like mine to clear....ones that user the eeprom for data storage wouldn't. Just not good to leave trash around. It wouldn't even have to be a two pass thing (clear eeprom, then write), that would fry faster. The compiler could just fill the BXB space up with nulls after the compile (user selectable characters strings... even better) and then download. The eeprom is written once, but fully clears/initialized to the nulls or string values. One could also do what David suggests then and hide keys and PINS in the user character patterns a little easier and not have to mess with the actual code segments. One could even place copyright information as the pattern text mask. .db. -----Original Message----- From: Dave Houston [mailto:] Sent: Monday, October 29, 2001 4:27 AM To: Subject: Re: [BasicX] RE: RE: Software Download without BasicX downloader It may get wiped out if there is a "Verify Error" or other problem with the download. I use the upper 7K or so of EEPROM for data storage and it sometimes gets corrupted if there's an error during the .bxb download. The higher in EEPROM, the less likely this will happen but I would not trust that even the highest EEPROM locations might not get corrupted on occasion. On 29 Oct 2001, at 16:18, David and Megan wrote: > It leaves the rest of EEPROM alone. > > I tried using the eeprom key idea > ie place a PIN at the end of eeprom memory using one program > > The second program did not wipe the pin as it could compare a > reference to it. > > I know Dan said it's bad to have a big empty space at the end of > memory then the key, but what if we fill the eeprom with garbage first > and have the key hidden somewhere in the middle of it (where the new > program won't overwrite)? > > just a thought, > > Dave. > Message: 12 > Date: Sat, 27 Oct 2001 19:53:25 -0700 > From: "Dan Bielecki" <> > Subject: RE: RE: Software Download without BasicX downloader > > >> When you upload a new program to the BX, does it zero-out memory > >> beyond > the end of your > >> program, or does it leave the rest of the EEPROM with whatever was > >> there > before? > > John? Wow! ..just never thought about it really until this thread. > You really got something there.... Hummm...Im gonna go Peek and Poke > around a bit...see what gets barfed out. > > .db. > ------------------------ Yahoo! Groups Sponsor > ---------------------~--> Pinpoint the right security solution for > your company- Learn how to add 128- bit encryption and to authenticate > your web site with VeriSign's FREE guide! > http://us.click.yahoo.com/yQix2C/33_CAA/yigFAA/CFFolB/TM > ---------------------------------------------------------------------~ > - --- http://www.laser.com/dhouston/ Yahoo! Groups Sponsor Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. [Non-text portions of this message have been removed] |