AVRISP mkII need external voltage?

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Hi,
I buy a AVRISP mkII and connect to AtMega16
correctly...
But AVR studio give me that error

No target was detected. Ensure that target has power

i tryed to calibrate pin nr. 2(VCC) and 6(GND) for 5+, onutside off AVRISP, but the was 0V.

Now, need i a external voltage?
is anything wrong with my AVRISP?
or i am misunderstand, and AVRISP will not give AtMega16 any voltage and i must have a external voltage source!

Im very new in AVR :=) Thx

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Quote:
AVRISP will not give AtMega16 any voltage and i must have a external voltage source!
Correct, you must have your own power supply and MUST HAVE pin 2 connected to VCC for the AVRISP to detect it.

John Samperi

Ampertronics Pty. Ltd.

www.ampertronics.com.au

* Electronic Design * Custom Products * Contract Assembly

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js wrote:
Quote:
AVRISP will not give AtMega16 any voltage and i must have a external voltage source!
Correct, you must have your own power supply and MUST HAVE pin 2 connected to VCC for the AVRISP to detect it.

Ohh! Tanks for your answar JS!
I believed IC get power from AVRISP!
So i must connect a external power!?

I have 3 qouestion!

1- Why? Why cant we get 5V from AVRISP?
AVRISP get 5V from USB, and why cant AVRISP forward that to IC? USB voltage is very stabil!

2- Why need AVRISP voltage from output to?
For check about IC is on?

3- So i need a external power 5V+, and you si i must connect to pin 2, and pin nr 2 to VCC for IC?
I mean need both off them 5V?
pin nr 2 from AVRISP and pin nr 10 from my IC (AtMega16)...

I cant understand why AVRISP forward voltage to IC!
I tryed in 3days now with whink AVRISP well forward voltage to Atmega and i dont need any other ting!!!

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Quote:
Why cant we get 5V from AVRISP?
Because that's how it works. :? The STK500 can supply power to the target but not the AVRISP but only for small loads. Think of the problems you will get if the target board needs 1 or more amps of current. It may not be the case with your board and you need a power supply anyway after the programming is done.
Quote:
Why need AVRISP voltage from output to?
For check about IC is on?
Yes and also to see what voltage the target is working at as it can be from 1.8V to 5V so the programmer needs to adjust the programm voltage to suit.
Quote:
I mean need both off them 5V?
Yes all of the VCC pins and ground pins need to be connected both for the chip and also for the ISP header. If you want you can look up this diagram http://www.members.optusnet.com.... it is for the older chip but it is still pin compatible with the M16. (I will need to upgrade the old drawings one of these days)

John Samperi

Ampertronics Pty. Ltd.

www.ampertronics.com.au

* Electronic Design * Custom Products * Contract Assembly

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If you are only running 5V designs, and your target power is less than a few hundred mA, then you can open up the MKII and jumper the USB +5V to ISP connector pin 2. That way you can power your target directly from USB. Keep in mind that the USB +5V specification is pretty loose (+/- 10%) I believe. Most +5V logic should be able to handle that ok.

I've done this with one of my MKII's with no problems.

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js wrote:
Quote:
Why cant we get 5V from AVRISP?
Because that's how it works. :? The STK500 can supply power to the target but not the AVRISP but only for small loads. Think of the problems you will get if the target board needs 1 or more amps of current. It may not be the case with your board and you need a power supply anyway after the programming is done.
Quote:
Why need AVRISP voltage from output to?
For check about IC is on?
Yes and also to see what voltage the target is working at as it can be from 1.8V to 5V so the programmer needs to adjust the programm voltage to suit.
Quote:
I mean need both off them 5V?
Yes all of the VCC pins and ground pins need to be connected both for the chip and also for the ISP header. If you want you can look up this diagram http://www.members.optusnet.com.... it is for the older chip but it is still pin compatible with the M16. (I will need to upgrade the old drawings one of these days)

Ohhhh! I see.. Thank you man,
i understand now!
i get your point now!
Thanks a lot JS :=)
You help me really! i tryed to read all PDF file about AVRISP and many web sites, but ...

Last Edited: Sun. Jul 5, 2009 - 04:40 PM
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gahelton wrote:
If you are only running 5V designs, and your target power is less than a few hundred mA, then you can open up the MKII and jumper the USB +5V to ISP connector pin 2. That way you can power your target directly from USB. Keep in mind that the USB +5V specification is pretty loose (+/- 10%) I believe. Most +5V logic should be able to handle that ok.

I've done this with one of my MKII's with no problems.

THanks for your tips!
I have create a power supply with 7505,
so since am new, and tips from JC, so i think i use that power supply, and dont risk to broke AVRISP :=)

Thanks again :=)

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hehe i come with one other question!
need i external crtystal to?

know i need crystal (for frequency) in normal form without AVRISP, for puls.
But i think read in one website, about if IC is connect to AVRISP in ISP form dont need external puls.
So i dont need connect anything to Xtal1 & Xtal2.
IS this true?
Or i need external puls to?
if i need, which crystal i need to buy?

I work with AVR for the first time,
and all i well now is blinking led,
when Atmega is connect to AVRISP!!!
Just for learn how program this IC!

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For simple projects you can use the default 1MHz internal clock (or 8MHz if you turn off the CDIV fuse) but if you want to use the USART then it is better to start using a crystal. You can see how to wire it from the diagram above. The maximum frequency is 16MHz.

John Samperi

Ampertronics Pty. Ltd.

www.ampertronics.com.au

* Electronic Design * Custom Products * Contract Assembly

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Thanks man, i try to connect IC, and working right...
Both off led on AVRISP is green,
And in AVR studio can i read signature,
and no any error :=)

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Hello i have a question as im using Atmega in my project, where should i connect the power supply? to the vcc of Atmega or to the vcc of AVRISP ??sad 

 

Ragu

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The power supply should connect to the VCC along with GND as well, to your project.   The AVRISP mkii will need to sense that voltage via it's vtarget pin in order for it to set the correct interface voltage level drivers.   The doc for mkii is a good place to start on how to use it. 

 

Jim

 

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Welcome to the Forum.

 

If your micro has an AVcc pin, that pin will also need to be connected to the V+ of the power supply.

 

JC