ISP without AVCC ?

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#1
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Guys,

Is it possible for me doing ISP without AVCC connected ?
Any infos will be appreciated,

Thanks

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Why would you want to do this?? Avoid the issue and connect it.

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The chip, itself, will not work correctly without BOTH Vcc and AVcc connected.

Jim

 

Until Black Lives Matter, we do not have "All Lives Matter"!

 

 

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Ok, I see....
for Kartman, because the inductor I ordered online hasn't been arrived, I can't wait to test it....

Thanks for the info

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Then, for ISP, just put a jumper in place of the inductor.

Jim

 

Until Black Lives Matter, we do not have "All Lives Matter"!

 

 

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good idea....but I prefer waiting it since it's a bit mess to solder and desolder the jumper...

thanks anyway

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is it because I haven't put the crystal on it ?
but atmega128 has internal oscillator isn't it?

I got Chip enable error on USBASP

The connection :

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Quote:

is it because I haven't put the crystal on it ?
but atmega128 has internal oscillator isn't it?

Depends on whether you have changed the chip's fuses or not. As it's supplied to you it's enabled to use the internal RC at 1MHz so ISP should be possible. If you then used ISP and changed the fuses to say "use a crystal" but the crystal wasn't present then you would have a problem (see my tutorial about "locked out" AVRs if you are in this situation).

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OP said

Quote:
I can't wait to test it....

Patience is a virtue!

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I tested already with big SMD inductor and 24Mhz crystal,
it works allright, thanks guys

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Be aware, of course, that you are overclocking your M128.

It top clock frequency is 16 MHz, (8 MHz for the M128L).

JC

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yea, I know, just for a test, I want to know it's working....I have unsoldered 24Mhz crystal from it
thanks