Programming atmega644 in ISP with STK500

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#1
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Hi guys,

I'm a hobbyist, I wanted to create something with a GPS and a SD card, I found this project in internet:

http://frank.circleofcurrent.com/cache/gps_logger.htm

It includes the code and schematics.
I was trying to load the code to the ATMEGA644 but I have not been able to do it. I'm using AVR Studio, and I set up the STK to isp, but I always have FALING messages when I try to upload the code.
I would really appreciate if you guys could tell me like some main steps to program the chip.

Thank you!

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Not the best circuit, that is if this:
http://frank.circleofcurrent.com/pics/gps_logger_circuit.png is the circuit you are using. Where is the decoupling? Where is the reset pull up circuit?

Even if this did work it would probably reset quite often and do some stange things.

It might be able to still program, but without some decoupling capacitors near the mcu it may struggle and reset. I suggest you add some additional parts (reset circuit and localised power decoupling near the mcu) and then try programming again.

A pic of your circuit / protoboard would probably help the us give you some more assistance. Do you have a spare MCU?

oddbudman

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hey that's my diagram

The diagram was just to demonstrate where the serial lines go and where the SD card goes. I never actually build one that was battery powered, I just threw that battery-switch-capacitor bit in there to get the idea across that this could be made portable.

The reset switch doesn't really need a pull-up resistor, there's one built into the chip.

The one road trip I took this logger on, I used a 4.7V battery with a 3.3V regulator and decoupling caps, it worked fine.

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I presume that you have the mega644 in SCKT3100A3. And you have every jumper in the default position.

In Hardware tab: Set STK500 voltage to 3.3V and clock frequency to 3.68MHz.
In Main tab: Set Device to mega644 and ISP frequency to 460kHz.
Read Signature several times. It must be ok every time.

If the SD Card is connected, you must have R1 connected to 3.3V

If in doubt, just remove card from the drive when you are doing ISP.

David.

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In isp programming the reset pin must pulled externally high using a resistor around 4.7K.If included in the stk board then is ok,else it must be putted,at least when an isp MKII is used.