I am using a CX3 to bridge a MIPI camera to USB.
The CX3 is booting from SPI FLASH. There is no external I2C device connected.
In that case, do I still need the I2C pull-up resistors connected, or should it work without them?
The reason I ask is that my system works fine when I have the I2C resistors soldered in place (I see a live stream from the camera), but if I remove them, then the CX3 enumerates and appears in Device Manager, but I no longer see any images from the camera.
Solved! Go to Solution.
It is necessary to have pull up resistors on I2C lines of CX3. This is because the MIPI CSI-2 block of CX3 is configured over I2C interface as mentioned in section 1.4 of CX3 TRM. The CX3 TRM comes along with FX3 SDK and can be found in the following location:
C:\Program Files (x86)\Cypress\EZ-USB FX3 SDK\1.3\doc\firmware