Hi can i know the IC detail from read fuse bits like what is ICs brand or model?
Last Edited: Sat. Dec 9, 2017 - 08:45 PM
programmer to show me ICs signature
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karimi4511 wrote:
Hi can i know the IC detail from read fuse bits like what is ICs brand or model?
Surely if you have access to the chip to read the fuse bits then you can simply look at the part number on top of the chip.
Or if the number has been removed then you look at the chip programmer settings to know what chip you are reading from.
However, if you are asking what chip has these fuse settings (taken from a website)...
0x5A, 0x3C, 0xFF
...then the answer is no.
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AVR have "signatures" so you can certainly read the model that way but there's a bit of a chicken/egg situation here in that to read it you need to first know (a) that it's even an Atmel chip, (b) which model it is and hence (c) to which pins you need to connect an Atmel compatible ISP device in order to read the signature. If you know all that there's no point reading the signature as you already had to know what chip it was anyway!
For IC model the answers have been given above, but for
karimi4511 wrote:
what is ICs brand
surely, if you have written the code you already know the brand?
Both the instruction set and the signature byte layout is specific for the AVR. Thus, if you write AVR code for reading the signature bytes then you already know it's an AVR.
Hi your right but If it's not mine and my cases is Varied what do i do?
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karimi4511 wrote:
what do i do?
What do you do about what, exactly?
I think the situation has been pretty clearly & thoroughly explained - so what else, exactly, do you want to know?
What are you trying to achieve?
Describe your goal - rather than focussing on a (possibly flawed) step towards it: http://www.catb.org/~esr/faqs/sm...
im sorry i dont ask my question clearly i want to make a programmer to show me ICs signature thanks alot
karimi4511 wrote:
im sorry i dont ask my question clearly i want to make a programmer to show me ICs signature thanks alot
Just for AVR?
Basically you need to know what the chip is so you know where the power pins are and where the ISP pins are.
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Brian Fairchild wrote:
you need to know what the chip is so you know where the power pins are and where the ISP pins are
Absolutely - as clawson already explained in #16 #3.
EDIT
Corrected reference - should be #3.
But, now, see also #18
Last Edited: Mon. Dec 11, 2017 - 11:12 AM
yes i want to know its way to get the signature byte
I want to get IC signature byte do you know how?
Can you post a picture of the chip? In focus, please.
karimi4511 wrote:
yes i want to know its way to get the signature byte
As I've just asked in the other thread...with a programmer or with the program which runs on the AVR?
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karimi4511 wrote:
yes i want to know its way to get the signature byte
You study the chip's datasheet - that will tell you how to get the signature byte.
Or, if you already have a programmer, you study its documentation to find how to get it to do this.
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karimi4511 wrote:
I want to get IC signature byte do you know how?
RTFM - see #15
Last Edited: Sun. Dec 10, 2017 - 06:34 PM
Note that I do not reply to PMs asking for help, it's better to share the answer so that anyone needing the information in the future can find it.
In your PM you asked...
Quote:
hi can you tell what code use to get signature byte?
thanks
As an example, for the mega328P, see section 27.8.10 in the datasheet. You will need to write your own code, in assembler, to achieve this but there is all you need to know in that section.
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Brian Fairchild wrote:
... in the datasheet. You will need to write your own code, in assembler, to achieve this but there is all you need to know in that section.
But, as has already been pointed out in #3 and #4 and #9: in order to write the code, you already need to know what the chip is - so the code is pointless!
awneil wrote:
But, as has already been pointed out in #3 and #4 and #9: in order to write the code, you already need to know what the chip is - so the code is pointless!
Indeed but maybe the OP is doing something clever. Maybe they use the signature, and hence knowledge of what the chip is, to dynamically reconfigure their code. I can conceive of a universal bootloader that uses the signature to determine where to load the incoming code and how much flash it has to play with. Maybe a universal RTOS that uses the signature to know how much RAM, and hence how many TCBs, there is to play with. Or something using timers or USARTs where, instead of compile time conditionals the code just 'knows'. Who knows? Not me. We never lost control.
Actually, I rather suspect that what the OP is really asking for is how to use a programmer, something like a USBasp, to read the signature. We'll see. And don't forget, we're only 19 posts into this topic; it needs to run for at least another 31 before we get to the real question.
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Brian Fairchild wrote:
I rather suspect that what the OP is really asking for is how to use a programmer, something like a USBasp, to read the signature.
But even then you need to know what chip it is in order to know where the ISP pins are, and where the power & ground pins are.
awneil wrote:
Brian Fairchild wrote:I rather suspect that what the OP is really asking for is how to use a programmer, something like a USBasp, to read the signature.But even then you need to know what chip it is in order to know where the ISP pins are, and where the power & ground pins are.
Quite. I'm sure we'll get there in another 29 posts.
can you please try to explain in more detail exactly what you want?
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Brian Fairchild wrote:
karimi4511can you please try to explain in more detail exactly what you want?
@karimi4511: You need to explain your goal - what you are actually trying to achieve.
ie, why do you want to read the signature? Once you've done that, what will you do with it?
If we know what you're trying to achieve, we can help you with suggestions on how to get there ...
See: http://www.catb.org/~esr/faqs/sm...