AVR Tiny Shipped as a HVSP device?

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#1
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Hello all,

Background:
I am building a board with a ATTiny 84 on it (SOIC-14) but I cannot get it to enter programming mode. I built my proto circuit on the ATTiny88-DIP, which I had laying around. I programmed this with ISP and all was well.

Problem:
From some research, it appears that maybe the RSTDSBL fuse ships programmed for the ATTiny 84. Is this correct? I also have an STK500, but do not want to 'frankenstein' it with wires to program with SOIC if that's not going to work :).

Symptoms:
(1) MkII detects the target (solid green led)

(2) Cannot enter programming mode, for any frequency.

(3) Sometimes the PC loses connection with the mkII when trying to program

Additional Notes:
(3) Reset Pull-up is 1k.
(4) I have checked the wiring many times and it is correct.

Does anyone know of this fuse's default settings for the ATTiny84, and an easy way to wire it to the STK500?

Thanks in advance,
Justin Reina

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Quote:
From some research, it appears that maybe the RSTDSBL fuse ships programmed for the ATTiny 84. Is this correct?

No, it should ship unprogrammed.
Quote:
Does anyone know of this fuse's default settings for the ATTiny84

It is all in the datasheet in the Memory Programming : Fuse Bytes section.

Regards,
Steve A.

The Board helps those that help themselves.

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It is not clear from your writing what your real problem is and what you want.

Have you found t84s with RSTDSBL programmed from the factory? Or are you just making things up?

Is the problem (whatever the problem is) with your STK500 or ISP mkII?

Maybe you want to buy an STK505 top board for your AVR.

Maybe you want to rethink the 1K reset pull-up.

Maybe you want to consider app. note AVR042.

Maybe you want to re-think the cabling (esp. cable length, but all other connections, too) between your board and the programmer.

Stealing Proteus doesn't make you an engineer.

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Hello,
It appears the ground connection for my ISP header was on a ground plane 'island'. Connecting this ground to the board ground fixed the problem.

@ArnoldB:

Quote:
It is not clear from your writing what your real problem is and what you want.

Have you found t84s with RSTDSBL programmed from the factory? Or are you just making things up?

There may have been kinder ways to deliver your message. Not sure if you intended for that tone.

Either way thank you for your suggestions, all were good ones. My main concern was that although the manual states RSTDSBL ships unprogrammed, many online comments suggested this pin as a default I/O. Wasn't sure.

Thanks,
Justin Reina

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justinmreina wrote:
Either way thank you for your suggestions, all were good ones. My main concern was that although the manual states RSTDSBL ships unprogrammed, many online comments suggested this pin as a default I/O. Wasn't sure.

Rule of thumb:

The data sheet is correct. Online comments are often wrong.

I have never seen anything about a factory programmed RSTDISBL. The chip would be unusable.

David.

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justinmreina wrote:
There may have been kinder ways to deliver your message. Not sure if you intended for that tone.
I'll try to remember not to care about your problems in the future. I can't promise, but I'll try. Does that answer your question?

Stealing Proteus doesn't make you an engineer.

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Hello,

@David: That was my sentiment exactly. I have used Atmel 8-bit for more than a few projects now, so I was very confused as to why it wasn't working. This was my first try with a Tiny, so I was really reaching for an answer.

Turns out I just need to be more careful in my layout!

@ArnoldB: Thanks. I guess. You seem like the kind who makes children cry. But then they deserve it for the naivety, I guess?

-Justin

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Quote:

many online comments suggested this pin as a default I/O.

OK, I'll bite: Perhaps you can point to a few of the "many" online comments that suggest this?

(sounds like an "urban legend")

Lee

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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Ok, I will confess it was only two. And one was strongly inferred on my point.

-Justin

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Quote:

Ok, I will confess it was only two. And one was strongly inferred on my point.

And any link(s) to what "they always say"?

Lee

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.