manual control of cx3 i2c signals

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ScGr_289066
Level 5
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Hi All,

Can someone point me to documentation for the CX3's I2C controller.  Specifically, I am seeing one of the I2C chips on my bus not releasing SDA on power-up.  My hunch is if I clock SDA a few times it would release, but I don't know how to access the signals independently of the I2C controller in the CX3.  I don't see GPIO numbers for controlling the I2C signals independently of the controller.

Thanks,

Scott

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SrinathS_16
Moderator
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Moderator
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Hello,

CX3 has got the I2C pins (SCL & SDA) on GPIO pin numbers 58 and 59 respectively. This has not been mentioned in the CX3 datasheet but FX3 and CX3 are similar parts and hence, the GPIO numbers are common. The CyU3PDeviceGpioOverride() API can be used to switch the functionality of these pins from I2C to GPIO. Please refer to the FX3APIGuide.PDF file for details on using the API. Once, this API is called, the pins behave as normal GPIO pins and can be driven using the CyU3PGpioSetValue() API.

Best regards,

Srinath S

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SrinathS_16
Moderator
Moderator
Moderator
1000 replies posted 750 replies posted 500 replies posted

Hello,

CX3 has got the I2C pins (SCL & SDA) on GPIO pin numbers 58 and 59 respectively. This has not been mentioned in the CX3 datasheet but FX3 and CX3 are similar parts and hence, the GPIO numbers are common. The CyU3PDeviceGpioOverride() API can be used to switch the functionality of these pins from I2C to GPIO. Please refer to the FX3APIGuide.PDF file for details on using the API. Once, this API is called, the pins behave as normal GPIO pins and can be driven using the CyU3PGpioSetValue() API.

Best regards,

Srinath S

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Thanks Srinath, just what I needed.

Scott

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