Voder wrote:
Let's put the limiters on the GPIO of the Raspberry (although this is the least important whether the Raspberry or avr etc). A switch on the top down to another GPIO of the Raspberry, and another GPIO to a relay with two NO outputs, or two NO relays. The controller will be the raspberry - something has to control these roller shutters after all. It will also be able to control, for example, LEDs when it has free ports. And if I add some Domoticz to it, it won't be a roller shutter controller anymore? :o
As for the raspberry, you might want to consider adding a buffer power supply from the battery.
Unfortunately, this type of computers with linux bootable from SD card on board are quite sensitive to power surges - during a sudden power outage, file system errors may appear on the SD card, which after rebooting the computer will require manual fsck in root mode (the system then does not boot, but waits for user action) - personally this happened to me several times.
The second thing about the Raspberry - it will not directly handle an LED or a relay (too low current capacity of the port) - you need to give intermediate buffers.
From my side, I can recommend Micropchip's I2C/16bit expander - MCP23017. Port load capacity up to 20mA.
Up to 8 chips can be connected to one I2C bus, which gives 128 I/O ports