SPI Problem AT32UC3B164

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#1
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Hi,

 

I have an SPI code, which works fine with AT32UC3B0256 on EVK1101. I've built my own board with the AT32UC3B164, and the problem that I see is that MOSI stays high. The CS and CLK are present. The MOSI is showing some ripples when it supposed to send the data. I measured the resistance between VCC and MOSI and GND and MOSI on both boards, and it's the same, 100K. Is there something that I'm missing.

 

Thanks for all help.

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Is the MOSI pin on your board the same as what is on the EVK1101 ?
ie. check the GPIO multiplexing.

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Yes, the GPIO multiplexing is the same. I've even replaced the AT32UC3B164 microcontroller on my board, but there are still same results. While the chip was removed, I used CLK, MOSI, CS from the EVK1101, and the board worked fine. Is there anything else that I should check?

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If the SPI pins are the same and the firmware is the same then it seems to me to be a power problem.
Are all the VDDIO, VDDCORE, etc pins connected and have power on them ?

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I've checked all the voltages, and they're present on the board. All the pin connections are made according to the datasheet.

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What I meant was, are *all* 3 VDDIO pins connected to 3.x volts, and the 3x VDDCORE pins connected to VDDOUT (or 1.8V) ?