The Amp Hour

By The Amp Hour (Chris Gammell and David L Jones)Science Technology Education How To Physics

Ranking
18th
on Physics
Favorites
65
Followers
Typical duration
66 min
per episode

Based on Podcast App listening data

The Amp Hour episodes

February 05, 2024Automating the Home with Keith Burzinski
Welcome Keith Burzinski of Nabu Casa and the ESPhome project!
Nabu Casa is a commercial venture that supports the open source Home Assistant (HA) project
Hardware
Home assistant allows your smart home to not require an outside connection, which is crucial to breaking free of large cloud providers.
Chris just got a Zigbee dongle and switched outlet working in under a minute on HA
Automation and triggers
Users share their automation routines on the HA subreddit
mmwave detecting heartbeat
What is esphome?
Abstraction / using YAML for business logic
Deciding when to go custom
Keith got started doing a PR for an IR remote
Nixie clocks
Boldport / Saar
Getting hooked on SMT builds
Keith made an STM32 based Tube Clock that Chris was very impressed by at a Chicago meetup
Keith reworked the sensing for his HVAC by fusing multiple custom sensor boards
Presence sensor - mmwave + IR sensor
Geodesic dome
Tiny fresnel lenses on low cost PIR sensors
Fixing thermostat in apt
Creating a network of temp sensors and weighing
SRE = site reliability engineer
Nabu Casa cloud service
The year of the voice
Home assistant YouTube
Hardware: Blue, yellow, green
How often are people reprogramming their devices
ESPhome discord
ESPhome.io
See devices that can be reprogrammed to work with ESPhome
Reddits
ESPhome
Homeassistant
1 hr 24 min
January 22, 2024Pneumatic Tubes, Straight To The Home
Dave just drove 4500 km / ~ 2800 miles
Dumpster room tier on Patreon?
Hyperloop failure
Florida train video (Wendover)
Pipedream
Series of tubes
Guam capsize
Hugo site builder, based on Go
Dreamweaver
Chris recommends buying a foldable lightbox (Light this)
Chris's blog post when he was going to meet Dave for the first time
Dehumidifiers are raising money based on ridiculous hype
Spec Sheet for Genesis Systems
Chris just got a chest freezer, was surprised at the low energy needs
Power charges
Texas grid article on NYT after recent deep freeze
Energy mix in NC
Beta voltaic
Used for aerospace
Bantam Tools (Bre Pettis) acquires Evil Mad Scientist (Lenore, Windell)
Vulnerabilities in the ESP32 RISC V parts
Will people make tools to make it easier to crack into something, like discussoned the CAN episode with Ken Tindell
Dave might get a free pick and place, the TVM920
Video about the 1980s "drink robots"
Chris's daughter is really into robots and gondolas
Pool robots videos on EEVblog2
1 hr 15 min
January 09, 2024The Twelfth Day of Keyzermas
Welcome back Jeff Keyzer of Mightyohm
Orthodox Keyzermas
Twelfth Day of Keyzermas
Jeff has been taking care of his ailing cat for the past years and learned a lot about administering medicine
RF
8753 / Copper mountain
Shariar sometimes features Copper Mountain VNAs on the Signal Path
Step attenuator
NanoVNA
Pallav Aggarwal articles
Murata modules
Chip down cellular
Seattle visit
The big dark
Input shaping
Printing with .25mm
Tek TM500
Scope on a monitor arm
Test equipment intervention
Jay Leno turbine car episode
Selling on eBay, including stuff made during the process of making parts for Jeff's equipment
Tek groups.io
Fluke in Seattle / now Everett
Vintage Tek Museum
Being set up to ship things
Shipping CRTs
CRTs are in vogue again (?!)
Low latency
Retropie
Oscilloscope music paying premium for RCA / Heathkit
Jeff was off to Hardware happy hour (3H) Seattle
Led Zeppelin had many references to Lord Of The Rings. Past guest and Chris's former roommate Steve Kreuzer was a huge LZ fan.
1 hr 21 min
December 19, 2023Pseudo Code...Pseudo Good
CES is coming up and there's good attendance as one of the last remaining large electronic shows in the US
Tradeshow are all bunched up in April for Chris in 2024, specifically Embedded World and Embedded Open Source Summit
Dave gives a synopsis of the latest Smarter Every Day video (about NASA)
Smarter Every Day video about NASA talk
Lunar lander training abort
Apollo guide SP287
Speeding up podcast...how fast can/do you go?
Last minute designs at the end of the year
ESP32 / NRF9160 board limitations
Cheap as chips - podcast about fish and chips
Siglent oscope SDS7000A
Innovators dilemma for car manufaucturers...and scopes too!
Kia Carnival
Kasm vs Codespaces
Home Assistant
ESPHome
YAML
NSW tour video / Quantum
Smart home fraturing
AI
New guide to Shenzhen, updated by Naomi Wu
1 hr 7 min
December 11, 2023Benjamin Cabé Nose Zephyr
Welcome Benjamin Cabé of The Zephyr Project!
Benjamin is the developer advocate at The Zephyr Project, which is both a Real Time Operating System and an ecosystem (or almost like a "distro", rather than an OS)
Benjamin does videos on the Zephyr YouTube and maintains an awesome blog / newsletter
The ecosystem is deep: Chris recently learned there is a state machine framework
Multiple people involved in dev like an OS
The Platinmum Members includes chip companies like NXP, Nordic, ADI
There are 600+ boards supported in the ecosystem (and more if you do custom)
Devicetree is a tough concept, but a powerful one that was borrowed from Linux
Who is the audience for Zephyr?
Chromebook embedded controller
What's the smallest processor that Zephyr can run on? M0s can run it no problem
Chris thinks one of the benefits is the ability to bolt new stuff on to a project
Simulation through Wokwi (Past Guest Uri) or Renode (Past Guest Michael)
Using different levels of abstraction
zephyr i2c init
Benefits of abstraction
Swapping out chips (bubblegum tapshoes)
Tying stuff together (bolting stuff on)
Infrastructure with CI/CD
Zephyr doesn't have an official IDE but VScode "just works"
Helper tools from Nordic
Open Source
Hobby projects
Dev survey
Custom Keyboards (ZMK)
RP2040 support
Arduino recenlty joined the project
Layers of abstraction
Architecture (ie. arm, nios2, x86)
SOC (available peripherals surrounding the core)
Board (PCB definition which might have:)
SOC
Memory
Peripherals / Sensors
Check the tree and PRs for sensors that might be in-flight
Compared to Arduino IDE
Choosing ecosystems
Weekly newsletter
Things you didn't know you needed: NMEA subsystem
In Jay Carlson's 2nd appearance on the show, he said "I'm reading more code than I'm writing"
Benjamin's profile photo is of his artificial nose he created a few years ago
Making a machine model for bread (pandemic)
It uses TFLite
What is the project doing? (in parallel)
Acquire data
Machine learning inference
Display update
Network interface
Benjamin reimplemented the Nose in Zephyr using ZBus (Chris recorded a video with the author of this subsystem)
Like an MQTT broker on device
Some of the concerns I (Chris) had when I was starting was not understanding RTOS concepts (threads, queues, etc). Brian Amos was on the show talking about his book, which is a great way to get started with these ideas.
Threading / work queues
The importance of a project when starting out
Starter hardware
Hero devkits (Chris likes the nRF9160-DK as a starter board or the nRF5340-DK)
M5stack boards
iMX8
Jumping down to Zephyr from Linux
MPU + MCU
Tight integration
Zephyr can run POSIX code
What about the the RT in RTOS? Does this operate realtime often? (timing critical)
BOM cost and software cost
Security and dependencies
Join the Zephyr discord to talk to other people using Zephyr
TechTalks / YouTube
Interested in going to a conference in Seattle in 2024 for Zephyr? The ZDS / EOSS CFP is open now!
1 hr 7 min
November 28, 2023For a couple weeks there...
You may have noted a few weeks off in September...Chris was busy with a new kiddo!
Starship launch was awesome, but Blue Origin might beat them to market?
Chris has been troubleshooting some boards he had made recently. It was pre-baby so sleep deprivation can't explain some of the screw ups!
PCB Carolina was a local tradeshow
TechTechPotato talks about layoffs at SiFive. Article about the layoffs.
RP1 show
RetroPie
Oversupply in the market is hitting some silicon vendors
Dr Michael Burry (highlighted in The Big Short) has been shorting the semiconductor industry
At the end of the movie the epilogue talks about how Dr Burry is watching water as well, possibly why he's shorting semis?
Chris wondered if Steve Sanghi mentioned why they're still in Arizona while he was on the show
Nuclear Diamond Battery video
SnapEDA
"off by one letter" error while ordering parts
PCF85063BTL vs PCF85063ATL
Scotty does a tour of the WorldSemi (makers of the WS2812B) factory, it's awesome!
Ben Hencke of ElectroMage makes the PixelBlaze, which is a great way to drive LED strips
Dave was talking to past guest of the show, Andrea Morello, about future changes to Quantum computers
China is turning off exports of Germanium and Gallium, which could impact the upstream supply for the chip industry, including around specialty semis.
Breakdown
Bunnie writes about why the US shouldn't put restrictions on RISC V (agree!)
KiCon has happened in Europe and China now, check out the talks on the KiCad YouTube channel.
Future (distributor) was acquired by WT Microelectronics out of Taiwan
Check out this 1975 tour of a UNIVAC manufacturing plant
1 hr 8 min
November 21, 2023Learning Computing with Jeff Geerling
Welcome Jeff Geerling of the Jeff Geerling YouTube Channel!
Jeff sounds so calm one his videos because he records after the kids are in bed
He started working with dad at the radio station when there was a transition in radio to digital / online. Jeff had an early job as a technology explainer while making manuals at the station.
Jeff still makes videos with his Dad on the Geerling engineering channel
Ham radio vs broadcast
1 Million Watts on the Supertower
Calling the FCC
CamOX facility
Keeping people interested during videos
Mars 400
RPi clusters
It's a good exercise because it helps those building it understanding the limitation of spreading across computers
Drupal website on cluster
"The constraint gives me the story"
A good starter project? Maybe the project pi cluster
/r/homelab
NAS, monitoring, VPN, pidramble
Home Assistant
ESPhome
yaml files: better than xml, JSON is better
Devices should only be added to the house if they are: Local, additive, private
X10
Smart stuff in the house
Interested in the embedded side
LLM
Jeff became Chris's de facto Pi5 analyst
RP1 episode
PCIexpress
Jeff discusses RISC V
1 hr 4 min
November 13, 2023Accessible ASICs with Andreas Olofsson
Welcome back, Andreas Olofsson of ZeroASIC!
Andreas was on the show back in 2015 (ep 254) talking about the Parallela, a crowdfunded parallel calcuation board by his then-company Adapteva
What is enabling more open source to happen?
Unit economics really impact silicon designs
Open source effects have been having a positive effect on the industry. Andreas maintains a meta repo of 400 tools.
Fewer fabs than 2008, mask sets still expensive
Semiconductor singularity
Andreas is deep into the world of "chiplets"
This is the basis of his new company ZeroASIC
Before he started that he was a program manager at a little outfit called DARPA
Andreas focused on lowering costs, with the idea that 3 people should be able to design a chip
He worked under Bill Chappell, the director of the Microsystems Technology Office (MTO)
OpenROAD
POSH
CHIPS
TinyTapeout
Andrew Kang UCSD
Chiplets
We had Ming Zhang on to tlk about ZGlue, but that was a slightly different architecture
What is a chiplet?
AXI on chip
SERDES
Types of interconnect
Organic
Types of output
SIP, Chip, SOM
ZeroASIC is Andreas' latest company
They started by releasing a Silicon compiler project
New thing is take system customers and build them an ASIC
Optimizing speed and cost
Mostly targeting aerospace and defense
Try it out yourself on the ZeroASIC emulation page
Their main processor is a Quadcore RISC V
There are no off the shelf chiplets
eFabric Active Interposer
Defining a standard
arm made a standard called amba
AIB from Intel was opensourced
Getting external contributors (hardware vs software)
LatchUp - Fossi
Personal passion drives people to contribute
You're really buying a datasheet from a big company
Loading the design to AWS
Check out the ZeroASIC openings
Read about how ZeroASIC is democratizing chip making
1 hr 4 min
November 05, 2023History of the Cathode Ray Tube with Kathy Joseph
Kathy Joseph from Kathy Loves Physics joins Dave on The Amp Hour to discuss history and physics. They end up discussing the intricate history of the development of the Cathode Ray Tube.
Read Kathy's Book The Lightning Tamers: https://tinyurl.com/TheLightningTamers
Video of this recording: https://www.youtube.com/watch?v=CnJ7mQ_Fo-8
Forum: https://www.eevblog.com/forum/blog/eevblog-1577-history-of-cathode-ray-tubes-with-kathy-joseph/
1 hr 19 min
October 23, 2023The RP1 and beyond with the Raspberry Pi Hardware team
Welcome back James Adams and Liam Fraser
The RP1 is the new custom silicon on the Raspberry Pi 5 that is the helper chip to the Broadcom part onboard
The HW team was last on the show in 2021 talking about the RP2040
They have been working on the RP1 since 2015
It's a small team, especially compared to other companies doing custom silicon.
RP2040 update
Scripting to reconfigure the silicon clocks/blocks
Are they making other chips?
Divvy-ing up duties for silicon
Broadcom is making the processor and took input for this latest
Dialog/Renesas do the power chip on the RPi5
PIO
Chris gave an example of a board (the Ostentus) where the PIO is just listening for i2c messages and passing them up the stack.
Design goal was to do cycle by cycle processing
Someone on twitter having PIO talking to fiber transceivers
Sourcing and RP2040 availability
They get 20000 chips per wafer
Buying wafers a few at a time through IMEC, sometimes through TSMC directly
There are often small amounts of availability of "wafer starts"
TSMC40
IP block updates: USB 3 / Ethernet
Can do diffs on the verilog
Receiving high paid IP
Liam is the sysadmin / servers are on site
Buying from Synopsis
Stitching together IP
They list what version of the IP they're using in the various sections of the datasheet.
Prototyping on FPGAs
Controller and Phy interface are exposed
ProFPGA system with daughtercards
Can't run at full clock speed on FPGA
Digital vs analog simulation
Could someone (competitors) copy things?
As open as possible, being open where it provides value
Cost savings on the RP2040
Traditionally the "Southbridge" is the IO hub for computing, the Northbridge was the cache/memory (later subsumed into large CPUs)
2712 on RPi is 16 nm
This model of creating different generations of silicon but putting them all together is similar to chiplets but...on a PCB
There is a (hidden-ish) PIO in the RP1.
There will be more processing delays in RPI5 to deal with, but they won't be noticable because Linux is already pretty not-real-time
Hoovering up more functions in one chip
Layout of connectors changed again
Pins are created to be well laid out on the PCB
RISC V foundation
The stack / ecosystem isnt as mature
James' signature is under the USB3 connector
RPi5 is "the most raspberry pi raspberry pi" yet
1 hr 10 min