KM34Z50M connectivity problem

[harishvenkatach]

Hi,

     I am trying to connect the Freescale KM34Z50M to Cirrus Logic CDB5480 board. The CDB senses temperature and the KM controls a relay based on the temperature readings. The CDB senses the room temperature properly, but when I connect the KM TWR to it, the readings somehow get corrupted. I connect the pins 17,18,19,20 of SPI to the RX,TX,CLK and CS of the CDB respectively. Can anyone explain why this happens?

Thanks in advance.

[Hui_Ma]

Hi,

Could you provide more detailed info about the issue?

From the description, there without problem with SPI connection.

If the KM34 could read out the data from CDB5480?

If the KM34 could not get the data from CDB5480 board stably during the whole temperature range?

Thank you for the attention.

Have a great day,
Ma Hui

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[harishvenkatach]

Hi,

     When I use the CDB5480 board as a standalone, it is able to measure the room temperature. But when I connect the SPI ports with the TWR, it throws up strange errors, likely due to corruption of the registers.

Hoping for a solution.

Regards,

Harish Venkatachalam

[Hui_Ma]

BTW: I checked CS5480 datasheet, the Max. SPI clock is 2MHz.

Please check if KM34 SPI clock setting if in range of 2MHz.

Wish it helps.

[Hui_Ma]

Hi,

I checked the CDB5480 board, there with a C8051F342 MCU connects with CS5480 chip with SPI.

If you could try to remove the resistors of  R34,R35,R36,R37&R38.

After that,please try to use KM34 board connects with the CDB5480 board and check if it works or not.

Have a great day,
Ma Hui

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[harishvenkatach]

Hi Hui,

     Thanks for replying. The resistors are soldered onto the board. How do we remove the resistors?

Regards,

Harish Venkatachalam

[Hui_Ma]

Hi,

I don't have that board. I think using an electric soldering iron could do that .

Have a great day,
Ma Hui

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[harishvenkatach]

Hi Hui,

     Thanks for your help. I appreciate it.

Regards,

Harish Venkatachalam