I would like to program the EVAL-ADAU1452MINIZ via I2C from an MCU. I am following the this link how-do-i-create-the-microcontroller-code-to-interface-to-my-sigmadsp
I will not use the SPI for this project.
Also why removing the usb cable stops the DSP program even if the DC jack input is still providing the 6v DC input to the board ?
How can i cancel that ?
SigmaStudio and the USBi is connected to the reset generator on the eval board. This is so you can reset the part from SigmaStudio if you desire. The problem you are experiencing is because you are unplugging the cable. This removes the power from the USBi so now the reset line that was being held high can no longer be held high and goes low resetting the DSP. So you need to disconnect the USBi from the eval board using the ribbon cable instead of the unplugging the USB cable.
Now if you program the part using SPI from SigmaStudio and want to switch over to I2C control you will not be able to do it. The slave comms port wakes up in I2C mode then is placed in SPI mode by SigmaStudio. Once in SPI mode it cannot be changed back without resetting the part. Then there is the issue of the SPI lines connected to the USBi. The USBi needs to be disconnected. Then you need pull-up resistors. I expect those are on your controller board. Disconnect the controller board when trying to use SPI because those pull up can cause issue with SPI. The two formats are not hardware compatible.
What you could do is use SigmaStudio to program the EEPROM. Then remove the USBi, reset the eval board so it boots up using the EEPROM and then connect the controller board that has I2C pull up on the board. Then you can communicate.