ATMEGA32 faulty?

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I have had big problems trying to get my avrisp mkii to talk to my atmega32.

I keep getting a blinking orange led.
Initially thought the problem was the reset which was at 1.3v, I changed it to 0.8v - no luck.

Pin 6 (PB5 MOSI) is sitting at 5v when just powering the MCU. I don't have a comparison with a known working mcu so can someone confirm this is suspect and can I assume the MCU is shot?

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OK answered my own question.

Got my hands on a working atmega8535, on MOSI and MISO with a scope you can clearly see data.
The avrisp mkii works fine.

On the atmega32 the MOSI is just held high even if you hold reset.

I doubt there is anything on can do program wise to achieve this so I guess the MCU is knackered.

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Hello & Welcome to AVRFreaks.

Quote:
Initially thought the problem was the reset which was at 1.3v, I changed it to 0.8v

How is the MCU connected? You can just connect the RESET line to the AVR-ISP to control it.

Did the Mega32 ever work? There are a number of fuses you could have changed - most likely an oscillator fuse, requiring you to connect an external oscillator. Possibly the SPI disable fuse if you / someone else used another programming method before...

If you disconnect the AVR-ISP, and hold the device in reset (ground the RESET pin), what is the MOSI then? The AVR-ISP should be driving the MOSI (Master Out Slave In) pin.

Use a 10K resistor and see if you can pull the pin high & low. If you cannot do that perhaps the device is damaged...

-Colin

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Thanks Colin appreciate the advice as I am quite new to this environment (as if you can't tell :P )

The kit was passed onto me by a friend.
Basically the controller board is on supplied by futurelec and is the older atmega32 controller.

It came with an old parallel programmer which I could not use.
I made the mistake of thinking the ISP port was standard, should know not to assume.

Fortunately the AVRISP MKII is not damaged.

So basically I have no idea what happened with this MCU in the past and don't know if it ever worked.
I retrospect this is a very bad idea when you are learning something new as it introduces lots of unknowns.

I will pull the MCU and test as you suggest.

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Quote:
It came with an old parallel programmer which I could not use.
I made the mistake of thinking the ISP port was standard, should know not to assume.

Most actually are. But there is no guarantee unfortunately! There is a standard for both the 10-pin and 6-pin header size, but it's just "common courtesy" that people follow this of course.

Do you have a model number on the board or anything?

-Colin

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The board is the one found here:

http://www.futurlec.com/ATMegaCo...

This board must be at least 6 years old and strangely enough the ISP is the only header not in the documentation. I would think this would have been fixed by later boards from futurlec.

I traced it out to this:
1 NC
2 MOSI
3 NC
4 MISO
5 NC
6 SCK
7 NC
8 RES
9 VCC
10 GND

Having replaced the MCU I am in business and have uploaded my code.

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Hello,

Hmm.. that IS an odd pinout. The normal one to use is shown at:

http://avr.tjerkdegroot.nl/image...

Glad it worked out though.

-Colin