MCU Serial Bus Sharing

Discussions focus on sharing I2C, SPI, UART, and PWM peripherals across multiple microcontrollers and even Intel chips, including challenges with voltage levels, optoisolators, level converters, pinouts, and protocol comparisons like I2C vs SPI.

📉 Falling 0.5x Hardware
2,853
Comments
19
Years Active
5
Top Authors
#9622
Topic ID

Activity Over Time

2008
3
2009
13
2010
12
2011
16
2012
37
2013
57
2014
88
2015
111
2016
148
2017
132
2018
141
2019
130
2020
297
2021
334
2022
305
2023
346
2024
359
2025
295
2026
29

Keywords

e.g SPI GPIO CD HDL PIO OMAP L611 TMK I2C pins signals bus port voltage serial circuit peripherals devices device

Sample Comments

sebazzz Jun 27, 2023 View on HN

Wouldn't a bunch of logic level converters resolve that?

pomatic Oct 5, 2022 View on HN

I2C perhaps? Fewer wires than SPI.

nikau May 10, 2025 View on HN

Would be surprised if they didn't have optoisolators to cater for that scenario

bhouston Jan 6, 2019 View on HN

The peripherals are all i2c, pwm, spi or uart? So they are shared between all microcontrollers and even intel.

gorkish Mar 19, 2024 View on HN

The irony of an 8-bit wide serial bus.... %-#

mikewarot Sep 28, 2023 View on HN

It's sad that a 5 volt powered device can't natively talk to the entire world of 5 volt logic peripherals.

boomlinde Dec 11, 2019 View on HN

Wouldn't you have to at least wire the chip select pins somewhere distinct for that to work? I know little about electronics.

mfgs Apr 19, 2019 View on HN

You'd need opto-isolated data lines. I can't see any common devices having that.

syntaxing Apr 13, 2021 View on HN

Interesting, is the pullup resistor common for other protocols like SPI?

chimpontherun Oct 7, 2025 View on HN

Which is kind of sad, since the Uno pinout is horrible for high-speed signals