Are there any resources available for modifying the Bela cape? I want to try and build my own custom cape with a couple different components, mostly to reduce the size and cost. I took a good look at the schematics posted on the Bela github, and it seems that the cape itself is just I/O and ADC/DAC. However, I have tried in the past to compile a program without the cape on, and it seems that the software checks for the cape before going forward. Is there anything I need to ensure so that a custom cape will work similarly to a normal one?
Building a custom cape
ebai101 Are there any resources available for modifying the Bela cape?
No, just the schematics, PCB and BOM (...) 
Oh, and our consultancy services, drop us a line at info@bela.io if you are interested.
ebai101 However, I have tried in the past to compile a program without the cape on, and it seems that the software checks for the cape before going forward.
Without the cape on, the program fails to initialize the codec and therefore stops. There is no check for the SPI peripheral. As long as you use the same codec on the same pins, you should be fine.
Awesome, thank you for the info. If I didn't include the AD7699 and AD5668 chips on my board, would I be able to use the analog ins on the Beagle in a Bela program?
You should be able to, using the regular linux API, but not from within the audio thread
5 months later
giuliomoro Hey, reviving this old thread. I've built a cape for the Bela Mini based off of the schematics, which omits the ADC, using just the codec. The codec does appear to be detected, I don't get an Error: unable to initialise audio codec like I do when no cape is connected. However, I'm getting PRU interrupt timeout, -1 110 Connection timed out with our cape connected, which I assume is due to a communication error with one or both of the peripherals. Is this because it is attempting communication with the ADC?
Of course, it could be a hardware bug on my end - are there some function tests I could run to test the codec?