SPI Troubles with megaICE and AVR Studio

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Has anyone encountered any problems with the SPI bus when emulating a mega103 using the megaICE with AVR Studio?
When I try to read from the SPI during emulation this process always fails when looking for a returned 'sucessfully read' byte.
This means my product cannot read its defaults on power up - rendering it useless.

Programming my target board directly, with the exactly the same code works fine, does anyone know of any problems with the megaICE reading the SPI for this device?

Best Regards,

Ric Sharp.

p.s. I've tried forcing my code through but I require a full and proper read from SPI.

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Are you running the ATmega103 in master or slave mode? We have seen this behaviour occure sometime in slave mode because of noise on the SS line.

Check the SS line with a osilloscop to see if the POD cables are picking up noice - giving you trouble.

rgds
Arild

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Hi Arild,

thanks for your reply,

I recognise that there is a known problem with these devices when running in slave mode but I am running in Master mode.

Also, I have monitored the SS line and there is no significant noise level to detect, I did however see some oddities and wondered if you know if this is due to the line tri-stating?

do you have any other suggestions? any help greatly appreiciated,

Regards,

Ric.

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