Hello! Best regards From Chile.
I Would like to ask about SPI protocol. Hope you can help me.
Well, I'm working on a MIDI controller... I'm using a Arduinos main uC to control 4 cascade 74hc595 shift register's using SPI to manage a 7segment display and some RGB leds so the user can know if it is on preset A from bank 1, 2 or 3. (I'm taking care of the current draw to not exceed the 595 limit)
The main concern is about the UC SPI lines... MOSI, MISO and SCK... Do I need to buffer them? how much current is being involved on SPI lines?
The buffers that are available on my country can only source 8mA. Should this be enough to drive the SPI lines to the 4 shift registers?
I hope I have made myself clear!
Thanks so much for your help and knowledge. Stay safe!