I'd like to make a small "MCU" consisting of a camera, a mic, some LEDs, and probably a cheap ARM CPU. I'm calling this my "SMIC" (streaming media IC).
I'd like to connect this SMIC MCU to a Raspberry Pi, and then write software for the Pi that can communicate with the SMIC. This software should be able to power the camera on/off, power the microphone on/off, turn LEDs on/off, etc.
Is this even possible? If not, why?!? If so, how?!?
I assume that I'll need the following setup:
- A homegrown device driver installed on the Pi for communicating with the SMIC
- A homegrown device driver installed on the SMIC for communicating with the Pi
- Homegrown "user" software on the Pi for issuing commands to the SMIC
- When the user software wants to, say, turn a green LED on, it must communicate with the device driver somehow
- The device driver, then must somehow communicate with the GPIO pins
If anything I have assumed is incorrect, please correct/clarify for me!
Assuming I'm more or less on track, then my real question is:
How does the user software send the
TURN_GREEN_LED_ONsignal to the device driver, and how does the device driver relay that command on to the actual GPIO pins?
I guess I'm just having a tough time seeing the forest through the trees here. Thanks in advance.