STK500 Will not enter programming mode

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Good Evening All,

 

I believe we have a eureka moment....The Tiny26 (that worked on the "new programmers" had a 10k pull down resistor on the reset line. The non working ATMEGA168V had a 4.7k pull down on it. Once I changed to a 10k pull down the new STK500 programmers worked! Now I need to convince others to change the pull down value on the offending ATMEGA168V targets.

 

-jw666

 

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I hope you don't really have a PULL DOWN resistor on the reset line!!

John Samperi

Ampertronics Pty. Ltd.

www.ampertronics.com.au

* Electronic Design * Custom Products * Contract Assembly

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Sorry! Pull up.

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 Here's an idea:

Does your circuit board share MOSI, MISO, SCK or reset with other chips or circuits (or have pulldowns, caps, etc on the lines?)   It could be the working stk is just barely able to program it, but maybe the new stk's can't quite handle the extra loads.

I'm sure this qualifies for a free t-shirt or fountain pen cheeky 

When in the dark remember-the future looks brighter than ever.

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so does that mean that you never checked the chip using the sockets on the board?

 

ref to #23 ?

 

 

Last Edited: Wed. Nov 8, 2017 - 06:21 AM
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jw666 wrote:
had a 4.7k pull down on it
Methinks you have not read AVR040?

 

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Sorry I didn't have the means to insert a 32TQFP​ in the socket.

 

-jw666

 

 

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But from your answer one would say that it can't be a problem with reset!!!
 

Add:

 

And how long would it take to solder the needed pins on a chip? 5-10 min and that would have worked

Last Edited: Wed. Nov 8, 2017 - 01:26 PM
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Clawson,

Obviously, I have not. Thanks

 

-jw666

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All,

Thank you all for your kind support.

 

-jw666

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