Accessing the Pinecil UART with Picoprobe

https://danielmangum.com/posts/risc-v-bytes-accessing-pinecil-uart-picoprobe/

by hasheddan • 2 years ago

46 30 2 years ago

fellerts4• 2 years ago

So apparently the Pinecil is a BLE-enabled soldering iron with a 108 MHz RISC-V processor running a custom real-time operating system [0]. The author wanted to access the UART logs, so they repurposed a Raspberry Pi Pico (a dual-core microcontroller system running a real-time OS) for the task.

That's a staggering amount of hardware, sortware and computing power devoted to decoding one of the simplest and oldest serial protocols from a device whose sole purpose is to essentially melt tin. Maybe I'm out of touch, but I think I'll stick to my thermostat-controlled Weller soldering station and FTDI UART converters. I apologize if this post comes across as snarky, my point is that these are solved problems and have been for half a century.

[0] https://github.com/Ralim/IronOS

ivoc• 2 years ago

FTDI chips cost at least $5 (https://www.findchips.com/search/ft232), but an RP2040 can be bought for less than $1, so it makes sense to use an RP2040.

tecleandor3• 2 years ago

Repurposing is also great. I have FTDI UART adapters that I've used once five years ago, and couldn't find them later, then had to buy another new one for using it (again) just once.

If I can take one of my rp2040s and use it for half and hour and then use it for a different thing, it's great

sebcat• 2 years ago

Doesn't the RP2040 require external qspi flash? What does that cost?

MCP2200 is ~$2.50 in single units and you don't have to deal with firmware or programming.

Denvercoder9• 2 years ago

There's other FTDI chips than the FT232, the FT230 can be found for <$2.

151552• 2 years ago

WCH CH340 USB-UARTs cost less than an RP2040 (and probably the external flash.)

https://www.lcsc.com/search?q=CH340

The reason to use an RP2040 is that you need a little bit of logic with that UART.

adolph4• 2 years ago

RP2040 is so cheap it is used in the debugger for the Pi Pico.

https://www.raspberrypi.com/documentation/microcontrollers/d...

tecleandor3• 2 years ago

Well, it's all solved problems, but the cheapest temp controlled Weller is over USD 200, and the Pinecil is 25.

The almost ubiquitous accessibility of cheap miniature general purpose microcontrollers/CPUs allows easy and fast creation of a device like the Pinecil, with a miriad of features: programmable PID, motion sensor, Bluetooth controller, temp profiles, battery powering, calibration, easy access to code... Cheap and fast. And it feels durable, not a toy.

And, if you don't have a FTDI UART converter or a logic analizer around, you just take an RP2040 from your electronic parts bin, and reprogram it. And once you finish, you can reprogram it for a different thing.

MrBuddyCasino• 2 years ago

To be fair, everyone who is into MCUs has a USB serial converter lying around, if not several. Or more snarky: repurposing a RP2040 is only free if your time has no value.

squarefoot• 2 years ago

Maybe I'm out of touch, but I think I'll stick to my thermostat-controlled Weller soldering station and FTDI UART converters.

Regarding FTDI products, after the well known controversy (1) I avoid them as much as I can. I also have two Wellers and will keep them until they die, which given their reliability should equal to never, but a few years back I purchased a Pinecil (1st model) out of curiosity and because I wanted to support Pine64 some way, and have to admit the device works really well even with non trivial joints that require a decent thermal mass (something many of those Hakko clones fail at). I have never installed anything onto it or even used any other function than plain temperature control though, but as a portable solder iron it just does the job without hitches.

1- https://www.reddit.com/r/amateurradio/comments/43q3vt/ftdi_d...

mtreis86• 2 years ago

I carried a butane torch soldering iron for years before the pinecil. I wasn't expecting it to have nearly the capacity but I've soldered some 8ga with it.

fecal_henge• 2 years ago

Its overkill but the BOM is probably a lot cheaper than whatever is running my Metcal station.

jLaForest• 2 years ago

You're missing out, pinecil is the best soldering iron I've ever used. I really like that it automatically turns off based on the accelerometer input when you set it down

dekhn• 2 years ago

I just switched from an old analog Weller to the Pinecel and I have to say it was a wonderful upgrade. The weller was retired to just do heat-set insert nuts, while I use the pinecel probably an hour or more a day, in short bursts. The fast heating ends up being very useful, and it just works, like the Weller just works. I don't modify any settings or talk to the processor.

adolph4• 2 years ago

I'll stick to my thermostat-controlled Weller soldering station and FTDI UART converters

How do you use an FTDI adapter to read from a Weller thermostat? What MCU is the thermostat?

fellerts4• 2 years ago

The thermostat is analog and dumb, no code involved. I don’t want my soldering station to run an OS, and I don’t want to program a Raspberry Pi when I need to interact with something over UART. In my mind, these tools are a means to an end, but I understand that people enjoy hacking on them.

poulpy123• 2 years ago

I know nothing about these things, what is the point to use a "smart" soldering iron instead of a normal dumb one ?

Graziano_M• 2 years ago

Well the most obvious is that you need some sort of smarts to drive the display. But also you can do a bunch of nice things (aided by a accelerometer):

1. Have custom temp profiles

2. Smarter auto on-off (e.g. cool down when placed down, heat up when picked up)

3. Flip the screen for lefties (I like this feature)

And anything else you can dream of.

stavros2• 2 years ago

There isn't much of a point. This just happens to be the best sub-$100 soldering iron you can get, and it costs $20.

Accessing the Pinecil UART with Picoprobe

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