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2009-06-24 by Kevin Madden
I have a automobile interface PC to PCM that I am trying to reverse engineer, the microcontroller is an ATmega 323L, I want to modify the firmware controlling the processor. I gave myself a quick lesson in ISP Programming. I now know that I know enough to get myself in trouble. I am looking for help and am willing to pay in order to avoid the inevitable pitfalls. any takers?
2009-06-24 by s.holder123@btinternet.com
Do you have access to any of the isp pins (MOSI/MISO/CLK/RESET) are there any pins brought out to connectors ? If so you can wire the pins to a AVRISP, and connect to it through the avr studio, at least you may be able to read the fuses and lock pins, it is more than likely protected or updated through a bootloader interface. The code may even be encrypted (.enc) do you have source code to compile or are you trying to read it from the device and modify from there ? Regards --- In AVR-Chat@yahoogroups.com, "Kevin Madden" <beechcraft_bob@...> wrote:
> > I have a automobile interface PC to PCM that I am trying to reverse engineer, the microcontroller is an ATmega 323L, I want to modify the firmware controlling the processor. I gave myself a quick lesson in ISP Programming. I now know that I know enough to get myself in trouble. I am looking for help and am willing to pay in order to avoid the inevitable pitfalls. any takers? >
2009-06-24 by ayman@elkhashab.com
On Wed, Jun 24, 2009 at 05:35:29AM -0000, Kevin Madden wrote: > I have a automobile interface PC to PCM that I am trying to reverse engineer, the microcontroller is an ATmega 323L, I want to modify the firmware controlling the processor. I gave myself a quick lesson in ISP Programming. I now know that I know enough to get myself in trouble. I am looking for help and am willing to pay in order to avoid the inevitable pitfalls. any takers? > > Well the first thing you could do is try to read the code out of the part such that you could modify it. However, more than likely the part is secured and you won't be able to read it at all. There really isn't an risk to trying to read it. On the other hand, make sure you don't erase it.
2009-06-24 by David VanHorn
On Wed, Jun 24, 2009 at 1:35 AM, Kevin Madden<beechcraft_bob@yahoo.com> wrote: > I have a automobile interface PC to PCM that I am trying to reverse engineer, the microcontroller is an ATmega 323L, I want to modify the firmware controlling the processor. I gave myself a quick lesson in ISP Programming. I now know that I know enough to get myself in trouble. I am looking for help and am willing to pay in order to avoid the inevitable pitfalls. any takers? As it happens, I'm up for some freelance work.
2009-06-24 by Dennis Clark
> I have a automobile interface PC to PCM that I am trying to reverse > engineer, the microcontroller is an ATmega 323L, I want to modify the > firmware controlling the processor. I gave myself a quick lesson in ISP > Programming. I now know that I know enough to get myself in trouble. I am > looking for help and am willing to pay in order to avoid the inevitable > pitfalls. any takers? Unless you are only trying to change a couple of constants in the code your odds of success here are pretty marginal. The code may not have been written in assembly, and assembly instructions are all that you will be able to read back. I've yet to see an assembly to C translator or assembly to Basic translator, depending upon the original language the developers used to create the code. DLC -- Dennis Clark TTT Enterprises
2009-06-24 by David VanHorn
> Unless you are only trying to change a couple of constants in the code > your odds of success here are pretty marginal. The code may not have > been written in assembly, and assembly instructions are all that you > will be able to read back. I've yet to see an assembly to C translator > or assembly to Basic translator, depending upon the original language > the developers used to create the code. Well, it's called a human being. :) Walk thru the asm, work out what's being done, and write new code. You can also try to work out what parts are the variables that need tweaking, if that's the problem. Question is, is it less expensive to just write it from scratch, knowing where the I/Os are and what it's supposed to do? -- There is no computer problem which cannot be solved by proper application of a sufficiently large hammer.
2009-06-24 by dlc
Exactly my point. DLC David VanHorn wrote: >> Unless you are only trying to change a couple of constants in the code >> your odds of success here are pretty marginal. The code may not have >> been written in assembly, and assembly instructions are all that you >> will be able to read back. I've yet to see an assembly to C translator >> or assembly to Basic translator, depending upon the original language >> the developers used to create the code. > > Well, it's called a human being. :) > > Walk thru the asm, work out what's being done, and write new code. > You can also try to work out what parts are the variables that need > tweaking, if that's the problem. > > Question is, is it less expensive to just write it from scratch, > knowing where the I/Os are and what it's supposed to do? > > -- Question with boldness even the existence of a God; because, if there be one, he must more approve of the homage of reason, than that of blind-folded fear. Thomas Jefferson ------------------------------------------------- Dennis Clark TTT Enterprises www.techtoystoday.com -------------------------------------------------
2009-06-24 by John Samperi
At 03:35 PM 24/06/2009, you wrote: >I have a automobile interface PC to PCM that I am trying to reverse engineer, > the microcontroller is an ATmega 323L, Post you home address while you are there, who knows, the company that designed the unit is likely be a member and will come and visit you and give you a hand. (broken or may be both) So the chips will most likely be locked, apparently you can get it cracked in eastern Europe for a few thousand dollars. Someone could get suspicious of you reasons. Regards John Samperi ******************************************************** Ampertronics Pty. Ltd. 11 Brokenwood Place Baulkham Hills, NSW 2153 AUSTRALIA Tel. (02) 9674-6495 Fax (02) 9674-8745 Website http://www.ampertronics.com.au *Electronic Design * Custom Products * Contract Assembly ********************************************************
2009-06-24 by Arao H. Filho
On my company all AVR microcontrollers that go to the market are locked,
reading them will get you a sequency like 123456....abcde.... try to read
it, if you see such type of data, it's locked.
2009/6/24 John Samperi <samperi@ampertronics.com.au>
>
>
> At 03:35 PM 24/06/2009, you wrote:
> >I have a automobile interface PC to PCM that I am trying to reverse
> engineer,
> > the microcontroller is an ATmega 323L,
>
> Post you home address while you are there, who knows, the company
> that designed the unit is likely be a member and will come and visit
> you and give you a hand. (broken or may be both)
>
> So the chips will most likely be locked, apparently you can get it
> cracked in eastern Europe for a few thousand dollars. Someone could
> get suspicious of you reasons.
>
> Regards
>
> John Samperi
>
> ********************************************************
> Ampertronics Pty. Ltd.
> 11 Brokenwood Place Baulkham Hills, NSW 2153 AUSTRALIA
> Tel. (02) 9674-6495 Fax (02) 9674-8745
> Website http://www.ampertronics.com.au
> *Electronic Design * Custom Products * Contract Assembly
> ********************************************************
>
>
>
--
--
Arao H. F.
MSN: ahf9920@hotmail.com
35-36213332 35-84360686 11-27122366
[Non-text portions of this message have been removed]2009-06-25 by Bob Paddock
> The code may not have > been written in assembly, and assembly instructions are all that you > will be able to read back. I've yet to see an assembly to C translator > or assembly to Basic translator, depending upon the original language > the developers used to create the code. Ida is good, I've used it in the past to work on some EDM machines where the manufacture was long dead. That was a few generations ago, Ida looks better now: http://www.hex-rays.com/idapro/ Even better might be the new product, that I've not used, http://www.hex-rays.com/decompiler.shtml to get you back to C faster. -- http://www.wearablesmartsensors.com/ http://www.softwaresafety.net/ http://www.designer-iii.com/ http://www.unusualresearch.com/
2009-06-25 by dlc
That's impressive. DLC Bob Paddock wrote: >> The code may not have >> been written in assembly, and assembly instructions are all that you >> will be able to read back. I've yet to see an assembly to C translator >> or assembly to Basic translator, depending upon the original language >> the developers used to create the code. > > Ida is good, I've used it in the past to work on some EDM machines > where the manufacture was long dead. That was a few generations > ago, Ida looks better now: > > http://www.hex-rays.com/idapro/ > > Even better might be the new product, that I've not used, > http://www.hex-rays.com/decompiler.shtml to get you > back to C faster. > -- Question with boldness even the existence of a God; because, if there be one, he must more approve of the homage of reason, than that of blind-folded fear. Thomas Jefferson ------------------------------------------------- Dennis Clark TTT Enterprises www.techtoystoday.com -------------------------------------------------