TarableCode

I remember having this exact issue then getting bored and distracted and moving on.
Wishing you better luck lol.

Trying to take pictures of the sky.

Great.
Totally fine that fetish posts appear not only in the discover feed, but on the main feed as well “from discover” in my main feed as well.

I won’t be reading this app in public anymore :(

IIRC it was the connector itself because the other board worked.

That is super likely to happen, so maybe I do need a different approach.
I'll probably end up back at 0603.

Unfortunately at the moment time and money are in short supply.
I definitely want to revisit it though.

I remember getting a bunch of parts to make my own, but I guess I got distracted.
The unmodified toaster oven remains in the closet.

Problem is that making proper software to handle reflow profiles was going to take too long and I couldn’t afford a premade controller.

There's probably a tonne of them out there, it's always just a matter of time, money, or both.
It feels like one of those things where to do it properly is going to cost $100+ in parts or hours of code plus $50 in parts.

That looks so cool but the price is far beyond what I can afford right now.
Someday...

All I have is a toaster oven, but I haven't gotten around to buying a reflow controller for it yet.

Just curious how feasible manual pasting and hot air soldering of 0402 parts is.
They look terrifyingly small.

What a ride…
On one board I lifted the usb connector because I’m clumsy, and on the other the bootloader button wasn’t soldered properly on one side.
Seems to be working fine now :)

I'm kinda curious to see what that looks like.

I think I found it...
Somehow GND is not connected properly at the very least since the board powers up (partially) through USB only if the ground is connected to my programmer.

I think I'll have to remove the USB connector to debug this further; especially that weird grounding issue.

The pull-up should be internal; I copied the design from my breadboard setup, but clearly something is awry.
I think I’ll have to pull off the usb connector so I can get a logic analyzer in there.

Come to think of it, it didn’t power up through usb unless via hub…
Something weird is up.

Close-up view of USB connector

Close up view of MCU pins

I'm kicking myself for not adding test points for USB, and now it doesn't want to enumerate for either TinyUSB or the built-in USB bootloader.

I'm not really sure what to do in this situation; USB is kind of a big deal for what I want to do.
Any thoughts?

A round TFT display on a round circuit board has a picture of nyan cat on it.

Yay: Part of my PCB works!
Noooooo: USB Does not!

External oscillator is now working :D
I had to lift it up using hot air, disconnect the enable pad and leave it floating.
I guess it really was active high after all. Whoops.

Shouldn't I be seeing something from the out pin though?
My first guess was the pin labeled "tri-state" with no other documentation is actually active high instead of active low as in my design.

Or I could just lift it and use the internal oscillator, but still I was certain I got it right :/

XOS32008000LT00351005 | TOGNJING | Price | In Stock | LCSC Electronics XOS32008000LT00351005 by TOGNJING - In-stock components at LCSC. Price from $0.1832. Free access XOS32008000LT00351005 datasheet, Package, pinout diagrams, and BOM tools.

The idea was to use an external oscillator instead of a crystal, but it's certainly possible I chose the wrong part and that's why.
www.lcsc.com/product-deta...

If so then, oof, that suuucks.
I could have sworn I spent extra time trying to get the right part.

Oh nooooooooooo there's nothing coming from the external oscillatooooorrrrrrrrr!

;_;

It's a ch32v203 with 128mbit spi flash on board and a connector for a round TFT display.
I had it assembled for me by JLCPCB, so if anything doesn't work its a whole lotta dough down the drain.

At least so far it programs and I get UART output, though the USB connector should've been further out

A round circuit board with soldered components

PCBs came and this one seems to program.
I’m a bit afraid of checking further in case I made a boat anchor, in which case I would be emotionally devastated for several hours to a day or so.

If I never actually test it then it’s possible everything works.

No worries; I played around with my footprint until I got something I was happy with.
In fact, the board just finished production and I hope to see it soon.

Would you mind sharing your footprint?
It looks like you even have the little holes for aligning the connector and everything.

Ohhhhh! I see it now!
That means I don't have to worry about placing components around the connector which I'm thrilled about.

My only worry would be doing a good enough solder job to survive the mechanical wear, but I'm definitely going to do this.

Much appreciated!

I'm having a hard time picturing it, do you mind explaining further?

A round TFT display aligned with a printout of a PCB

A closeup picture of a FPC cable next to its footprint

I have no idea if I’m doing this correctly or if I’m about to make expensive e-waste.

Anybody used these kind of ribbon cables or displays?

Pointless, but it was fun to try.

No idea if anyone finds this useful, especially since I need to fold in a few more controllers, but it supports a few as of now:

gc9a01
ili9341
ssd1351
st7735
st7789
st7796

All you need to provide is a few functions to set/clear CS,DC,RST and write to SPI.