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Re: [AVR-Chat] AVRISP -> AtTiny Communication Problem

2010-01-17 by Kenny M.

Well idiot down the street is making noise so I'm awake again... lol
I tried the 10k but no help.

If I don't connect reset to vcc ISP gives me the blinking orange light.
The same happens if I connect it to vcc with no resistor

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----- Original Message -----
From: "H. Carl Ott" <hcarlott@gmail.com>
To: "AVR-Chat" <AVR-Chat@yahoogroups.com>
Sent: Saturday, January 16, 2010 11:39:22 AM GMT -05:00 US/Canada Eastern
Subject: Re: [AVR-Chat] AVRISP -> AtTiny Communication Problem

On Fri, Jan 15, 2010 at 2:09 PM, Kenny M < kenny782@yahoo.com > wrote: 

> 
> 
> Sorry this post is a bit long. 
> I'm new to all this so be gentle LOL :) 
> 
> I'm working on my first project, which I've built and is working. 
> All that's missing is the chip to control it. 
> 
> I've got a few AtTiny15's and an AVR-ISP v2 (usb) 
> 
> So built a target board and connected all the programmer pins to the 
> appropriate pins on the chip. 
> I also connected my 5V+/Gnd to the chip. 
> 
> Now this is where I get confused, 
> I've found so many different schematics on the net... 
> 
> 1) This one just says connect everything as above and program 
> 2) Run a 4.7kohm between reset and vcc. 
> 3) Run a 4.7kohm & 10uf between reset and vcc. 
> 4) Run a 4.7kohm & 22pf between reset and vcc. 
> 5) Run a 4.7kohm & 10uf between reset and vcc, and an 800ohm resistor to 
> all the other connections. 
> 
> Unless you have some serious noise problems you don't need any cap on 
reset. 
You may or may not need a resistor to vcc ( I have to check the data sheet), 
but a 10k resistor will work, and will not cause any problems. 
4.7k should also work, but the value is a little low for ISP. 

Check your ISP programming speed in studio. It must be less the 1/4 your 
AVR's clock speed. 
And double check all your connections. It always seems tricky getting this 
stuff to work the first time. After a while it gets easier (well, 
mostly/usually/hopefully). 

> __._,_.__ 
> 

-- 
carl 
-------------------------------------------------------- 
Henry Carl Ott N2RVQ hcarlott@gmail.com 

[Non-text portions of this message have been removed]

Re: [AVR-Chat] AVRISP -> AtTiny Communication Problem

2010-01-17 by H. Carl Ott

On Sun, Jan 17, 2010 at 2:32 AM, Kenny M. <kenny782@yahoo.com> wrote:

>
>
> If I don't connect reset to vcc ISP gives me the blinking orange light.
> The same happens if I connect it to vcc with no resistor
>
>
Not sure I quite understand that.

Initially, you should hook up the chip to the isp signals.

mosi-mosi
miso-miso
sclk-sclk
reset-reset
gnd-gnd
vcc-vtg

reset also goes to vcc via 10k resistor (not necessary for all avr device
types but won't hurt)
NO other circuitry should be connected to any of the signal lines (at least
for now).
provide proper power (vcc and ground).

in avrstudio,
set isp programming speed to lowest possible setting
set correct device
set low voltage isp mode

If at this point you can't read the signature bytes, you've got:
bad wiring
bad chip
bad power
bad isp programmer

time to break out the scope.

-- 
carl
--------------------------------------------------------
Henry Carl Ott   N2RVQ    hcarlott@gmail.com

[Non-text portions of this message have been removed]