# The Spark Gap - Episode 18

- Show: [The Spark Gap](https://hardwarepodcasts.com/podcast/the-spark-gap)
- Published: 2014-10-15
- Length: 47m
- Page: https://hardwarepodcasts.com/podcast/the-spark-gap/2014-10-15-the-spark-gap-episode-18
- Listen: https://thesparkgap.net/the-spark-gap-episode-18

## Summary

Hosts Karl and Corey provide a technical overview of four common serial communication protocols used for chip-to-chip communication: UART, SPI, I2C, and CAN bus. They compare the protocols based on their wiring requirements, speed capabilities, duplexing modes, and signal integrity characteristics, noting that UART is simple but asynchronous, SPI is fast but point-to-point, I2C is multi-device but power-hungry due to pull-up resistors, and CAN bus offers robust differential signaling for noisy environments. The discussion highlights specific engineering trade-offs, such as the capacitance limits of SPI, the voltage level translation challenges in I2C, and the bus arbitration mechanics of CAN.

## Chapters

- [0:00](https://hardwarepodcasts.com/podcast/the-spark-gap/2014-10-15-the-spark-gap-episode-18#t=0) Introduction to Serial Protocols
- [1:11](https://hardwarepodcasts.com/podcast/the-spark-gap/2014-10-15-the-spark-gap-episode-18#t=71) UART: Asynchronous Communication and Baud Rates
- [13:31](https://hardwarepodcasts.com/podcast/the-spark-gap/2014-10-15-the-spark-gap-episode-18#t=811) SPI: Master-Slave Architecture and Speed
- [22:15](https://hardwarepodcasts.com/podcast/the-spark-gap/2014-10-15-the-spark-gap-episode-18#t=1335) I2C: Open-Drain Bus and Voltage Translation
- [33:11](https://hardwarepodcasts.com/podcast/the-spark-gap/2014-10-15-the-spark-gap-episode-18#t=1991) CAN Bus: Differential Signaling and Arbitration
- [44:06](https://hardwarepodcasts.com/podcast/the-spark-gap/2014-10-15-the-spark-gap-episode-18#t=2646) Engineering Gotchas and Conclusion

## Topics

- [Embedded firmware](https://hardwarepodcasts.com/topic/embedded-firmware)
- [Microcontrollers & dev platforms](https://hardwarepodcasts.com/topic/microcontrollers-and-platforms)
- [PCB design & layout](https://hardwarepodcasts.com/topic/pcb-design)
- [Debugging & failure analysis](https://hardwarepodcasts.com/topic/debugging-and-failure-analysis)

## Most relevant to

makers and hobbyists

## Mentioned

- UART (other)
- SPI (other)
- I2C (other)
- CAN bus (other)
- FTDI (company)
- NXP (company)
- Analog Devices (company)
- RS 422 (other)
- RS485 (other)
- LVDS (other)

## Related episodes from other shows

- [A Noisy Rude Bus](https://hardwarepodcasts.com/podcast/the-amp-hour/2023-05-08-a-noisy-rude-bus) (The Amp Hour)
- [2: My Little Pony Stopped Outputting](https://hardwarepodcasts.com/podcast/embedded-fm/2013-05-23-2-my-little-pony-stopped-outputting) (Embedded.fm)
- [362: Permutations of Underscores](https://hardwarepodcasts.com/podcast/embedded-fm/2021-02-18-362-permutations-of-underscores) (Embedded.fm)
- [Mute Button Discipline](https://hardwarepodcasts.com/podcast/the-amp-hour/2022-05-16-mute-button-discipline) (The Amp Hour)
- [Pseudo Code...Pseudo Good](https://hardwarepodcasts.com/podcast/the-amp-hour/2023-12-19-pseudo-code-pseudo-good) (The Amp Hour)

## Citing this page

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