#hardwaredebugging

Metro RP2350 take 5 🔄🌟🤞

Espressif programmer test success! 💻✨🔧

While developing boards, there are oftentimes we want to program ESP chips without going through the onboard USB port; this adapter will help us (and others) do that! It has a CP2102N USB-serial chip

https://www.digikey.com/short/bm7n3p5z

...with RX/TX signal LEDs and two transistors wired up to the DTR/RTS line for the 'esptool standard' reset procedure technique. The output IO, plus a 3.3V 500mA regulated output, is available on a socket header, so you can plug wires in for quick programming and debugging. You can use this for everything from an ESP8266 up to the ESP32-P4! Here, we are testing it with a HUZZAH ESP8266 breakout board

Ladyada's desk gets a scope cart

We've always wanted a portable scope cart

for our workspace to have our test equipment either by the desk for firmware work or at the soldering worktable for rework debugging. At our new office, we finally have space for one! We picked up this 'dental cart'

- It is not super fancy, but it is metal, and it came together fairly easily. We like the mini top shelf for the scope and the second shelf underneath for the power supply and electronic load. The drawer can hold leads or probes. We've locked it next to our desk so we have more desktop space, and it's easy to peek over as we bring up new boards like the metro RP2350

PCB troubleshooting and testing help engineers identify faults, verify electrical performance, and ensure reliable circuit board operation before deployment. By checking voltage levels, signal stability, component functionality, and connectivity using advanced testing tools, engineers reduce failures, improve product quality, and ensure long-term electronic reliability.

Having trouble with your Forlinx AM62x development board?

Our latest troubleshooting guide covers common interface issues including power checks, I2C & SPI communication, USB & SDIO signal integrity, and more!

Get practical tips to quickly diagnose and fix boot failures and interface glitches.

Perfect for embedded developers working with OK62xx-C boards.

You know that moment when you're 47 Chrome tabs deep into "research" (read: watching YouTube tutorials for hobbies you'll never start while simultaneously checking email, Reddit, and that one website where people draw mustaches on renaissance paintings), and suddenly your USB mouse decides it's had quite enough of this digital circus and ceremoniously disconnects itself?

It's not being dramatic. It's not mercury retrograde. It's a genuinely fascinating hardware quirk that exposes the precarious timing ballet happening inside your computer.

What's Actually Happening

What I've discovered through extensive analysis (and by "extensive analysis" I mean "becoming irrationally angry at my mouse and diving into kernel logs") is a delightful system architecture quirk:

When Chrome tabs consume significant CPU resources (mine were cheerfully gobbling ~44% each), the system experiences microscopic delays processing USB interrupts. For most devices, these delays are inconsequential—like being one person behind in line at the coffee shop. But USB mice, especially low-speed ones, are the technological equivalent of that person who checks their watch every 8 seconds while waiting for the elevator.

The error (-71 EPROTO) translates to: "I asked a question and didn't get an answer fast enough, so I'm disconnecting myself in protest."

The Class Divide of Input Devices

The most fascinating part? Your laptop's built-in touchpad continues working flawlessly during this mouse rebellion. This is because your touchpad lives on computing's equivalent of the Upper East Side—it connects through dedicated internal buses with VIP access to the kernel. When it speaks, the system listens.

Meanwhile, your USB mouse is essentially showing up to the party without being on the guest list, forced to communicate through the baroque bureaucracy of the USB stack, desperately hoping someone important notices its increasingly frantic message requests.

The Fix (Besides "Use Fewer Chrome Tabs" Which We Both Know Isn't Happening)

For those who refuse to close their 83 open tabs explaining why you should close your tabs:

#Tell your kernel to respect the mouse's feelings echo "options usbhid quirks=0x[your-vendor-id]:0x[your-product-id]:0x40" | sudo tee /etc/modprobe.d/usbhid-mouse-fix.conf # Boost USB interrupt priority

echo "options xhci_hcd interrupt=7" | sudo tee /etc/modprobe.d/usb-priority.conf # Refresh your kernel's perspective on life sudo update-initramfs -u

This essentially tells your system: "I don't care if Chrome is in the middle of rendering 47 JavaScript-heavy tabs about cryptocurrency—when this mouse speaks, you LISTEN."

The Broader Existential Crisis

The truly delightful thing about this issue is how it exposes the fragile assumptions underpinning our computing experience. We've built technological cathedrals on the digital equivalent of "well, it probably won't rain THAT hard."

So the next time your mouse vanishes while you're deep in a Chrome rabbit hole, know that you've stumbled upon one of computing's hidden fault lines—where timing-sensitive hardware protocols crash against the resource-hungry realities of modern web browsers.