Recently I've updated these with a new "Upside-down" view to complement the rear view, giving a pinout in the right orientation to match your project.
The Pico sites are all hand-coded single HTML pages with supporting CSS and minimal JS. They are set up to optionally install as a "Desktop" web app. They also degrade into a somewhat usable table in lieu of CSS and use vector graphics (for the board itself) to be viewable and printable at any size.
Finally, hidden behind "Advanced" is a pinout of the test pads and special function pins!
[1] - https://web.archive.org/web/20130505194305/pi.gadgetoid.com/... [2] - https://pico.pinout.xyz [3] - https://pico2.pinout.xyz
Thanks for your pimoroni [1] work as well, I've used quite a few products and they're always easy to work with because of good software and examples.
I keep a slightly modified version of it as a top comment in my main C file in every pico project. Super handy for quick reference and you can annotate it with the actual uses in your project.
ASCII-only really cuts to the meat of the problem though.
I especially love the ability to flip and reverse things, since I try to avoid comparing any two objects in different orientations, to cut down on mistakes.
It would be really cool if the community had a more general purpose open standard interactive diagramming tool for this sort of thing.
I guess the easy way would be to mark up photographs with pin locations, which would map to pins in a table, allowing for multiple tables in a document.
I'm not sure how you'd capture the data in a way that could be rendered to something like a screen reader or a more abstract diagram though, without a lot of complexity and edge cases.
Would it be enough to just verbally describe the mapping between pin numbers and the physical layout, as in "Across then down, starting at upper left", or would you need a meta data scheme for that?
There are a surprising number of pitfalls, since there's always some complexity most top-level diagrams don't reveal, but I feel is necessary to capture/avoid duplication of work- specifically, I mean documenting the pinout of the chip (RP2350, ATMEGA32U4, STM32H750, RP2 etc) and then translating that to a board layout.
I think the closest I've come is a prototype Pinout rewrite which started with chip [1] and board [2] JSON files.
Then, as you explore, there's the whole problem of presenting this information. I chose to capture information such as header type, orientation and pin-count but sometimes a header is too small (or there are too many headers) to document in-band so the kinda skeuomorphic presentation of the Pico pinouts doesn't work.
Perhaps that's where something like the minimap [3] from my "advanced" RP2350A pinout comes in.
Having a small representation of the board with the pin headers separate could work. It's been a while, IIRC a Fritzing [4] part involved creating a vector graphic of a part and naming the individual pin objects such that they could be mapped to a table of signals. I think SVG is compatible with this approach but... yeah, requiring people to create detailed board artwork (as good as it looks) is a stretch. The same could work for a good photo and just a table of offsets, as you suggest.
TLDR: This is a great idea and something I've wanted to do for ages. But I don't think I've got enough breadth of experience to do it alone.
1. https://github.com/pinout-xyz/pinout-2024/blob/main/chips/bc... 2. https://github.com/pinout-xyz/pinout-2024/blob/main/boards/r... 3. https://rp2350a.pinout.xyz
Maybe it could be paired with a basic image generator for common layouts?
Or maybe it could just have a set of selectable hardcoded layout engines, since "counterclockwise from upper left" and "across then down" cover a lot of things.
"Base64 of an images plus and offsets table" could just be a layout type, and people could submit PRs for anything else.
Maybe it could be something like: Your pin(or callout) Tables
Your Sections, which could have an image and some text
Your Images, that would either be literal pictures or rendering instructions that reference a table
So you could have a complete cheat sheet for any device on one page.
Will be an interesting experiment!
Pico never quite has a function where it’s needed.
Do you have a better workflow for this?
I'd love to have something that I can just feed a list of tags for each pin and have it pick the pins and make the layout in the fewest layers and/or with fewest vias possible (the latter would be amazing for making perfboard prototypes). Something like MCU_PIN1={uart1_tx,gpio_out,gpio_in,gpio_in_pullup...}, J2_PIN1={uart1_tx}, ... and then it just...figures it out and gives me pin table that I can use in the code (like a bunch of #defines).
At least that's my main pain point when working with microcontrollers. They give you like 20 pins and you plan out all the functionality and then it turns out that one of those pins is like an EEPROM pin that needs to be low at boot or linked to something else internally or some shenanigans like that and the idea is actually completely impossible to implement (looking at you ESP32-CAM lmao). Or PWM channel conflicts that set some specific sets of pins to the same frequency and the like. It would be such a great workflow step to be able to verify if something would theoretically work given the known limitations at least.
Microcontrollers are like if a PC had 4 USB ports and if you used two of them the third and fourth just stopped working cause nobody intended all four to be used at the same time. Absolutely maddening.
I’m currently failing to not build STM32Cube for Pico though, the idea keeps gnawing away at me. There are some idiosyncrasies that my micro site doesn’t quite capture. Though perhaps it could.
Bonus points if it could generate example initialisation code for the selected pins on the fly or maybe even an example snippet of code to get the peripheral going.
And code gen is something I'm looking at with the RP2350A pinout [2] where the JSON export would allow someone to plug it into any tool they like. (KiCAD symbol gen, C/MicroPython init code, etc)
It's difficult to strike a balance between features/minimalism but I'm increasingly drawn to the idea of a full (STM32Cube-like if you're familiar with it) configurator for Pico/RP2 based boards.
I have definitely struggled with making the Pinout spinoffs discoverable- the OG site had ten plus years to bed in.
