David, with all due respect, and to be perfectly and objectively factual, with no reasonable debate about it, Microchip TOTALLY BLEW IT on the flash part. Case closed. They blew it so badly that between the 77 and 77A, they completely revamped their fundamentally flawed design. They made some horrendous design decisions and committed them to silicon with the 77. It's a flash part, but if you want it flashable, it must be naked. If you want it secure, you must turn the flash into OTP. This couldn't be a worse situation. Now don't get me wrong, it is a great chip. As far as designing for the wrong part, this could not be further from the truth. It is what was available, and we designed for it. However, to overcome the chip's weakness, I'm at this very moment spending hour after hour on a mind-numbingly complex kernel that every thread must jump into code protected space and out again, to keep the code secure. And the encrypted bootloader? Unbelievably complex. All this wasted effort to overcome a very bad design decision by Microchip. And that the 77A was slated for release more than 7 months ago? Inexcusable. Basically, Microchip was aware of the code protect flaw but determined that a part that was selling well (the 77) didn't have pressure on the revision A to come out, what's the big deal if it slipped and people's code gets whacked by their respective mortal enemies? By the time the 77A ships, AFTER the 18F series, it will have been more than a year late. Why?? For a die shrink? Come on. And, beyond that, you can't even flip pages reliably with a single instruction, so it takes massive code space over the course of the code just to handle the flips. I will say thay by the time I'm done, at least 25% of the code space will be the page flipping instructions, and another 25% will be the mind numbing encryption algorithms. So my 8k chip is now a 4k chip, with only half of the lower 4k (open and naked flash memory) available for flash updates, which will be naked to ICSP reads once they land on the chip. So instead of 8k secure flash memory, 100% updatable, I get 2k of flashable memory that is naked to ICSP reads, and 6k of flash that is no longer flash, but is OTP. And I've got to grind off the chip markings to throw one more road block at some unknown hacker who may not even exist. What a joy! The fact remains that little old me is picking up the slack of a multi-billion dollar company that gave **no consideration whatsoever** to the fact that the ONLY part of their chip that is not a commodity is the code that resides inside. Defend that? NEVER!!!! -----Original Message----- From: pic microcontroller discussion list [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of David Dunn Sent: Wednesday, July 25, 2001 10:12 AM To: PICLIST@MITVMA.MIT.EDU Subject: Re: [PIC]: FINAL WORD: A great solution for the PIC16F877 problems (code protect,bootloader) i still think you're taking a fringe view on this. very few people use a bootloader in a production environment, so for 99% of everybody out there, including myself, thier code on a 16F877 is perfectly safe from all these evil hackers you refer to with the available-right-now code protection features. i'm sure since it won't do what *YOU* want it to do, and that's all *YOU* care about, it seems like it's a bad part, but i think you are out of line posting things like this. back in the real world, *YOU* are probably the only one having a problem because *YOU* failed to design with parts that are available. dld >So, if anyone is using the F877, you are stuck with the copyable flash and >memory-dumpable code protected region from pirate code getting past your >bootloader. Basically the chip is very, very weak and unfortunately is a >poor design. They've fixed it in the 77A and 18Fxx2, but it took forever, >and is stil not fixed for another 5 months. And, if weak chips get into the >stream, you can't close pandora's box. > >So, do your best, but know you are delaing with a weak chip. Darn!!!!! And >to think the 18F gave me that glimmer of hope, just to take it away again. >That was a mind screw I didn't need. The 16F877: great little chip, even >better for hackers and reverse engineers and code copyers. > >Ron -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads