I would like to connect 2 uC via NOR gate:
This is start phase, so no USART, TWI or SPI at the moment.
I need to detect positive impulses on uC 1, duration of 1 second.
INTERRUPT on uC 2 is active low.
My plan looks like this (in picture).
Few questions came to my mind:
1. About pull-up resistor R1
a)Do I actually need R1 or 1Y does do it for me(I mean if there are no pulses 1Y is HIGH)?
b)Can I internally enable pull-up resistor on INT 1 of uC 2?
c)Can I leave R1 as is in picture?
2. What should I do with other inputs on NOR gate and Y2 which aren't used?
a)2A 2B 2C 2D tie to GND and Y2 leave floating
b)2A 2B 2C 2D tie to Vdd and Y2 leave floating
Thing here is to minimize power consumption.
3. What do I need to do to minimize possible electro-magnetic interference on:
a) uC 1 <-> NOR gate side
b) NOR gate <-> uC 2 side
Other solution are welcome too!
Thank you, guys !