Friedland DC55 Window Sensor Reverse Engineering pt 3


My nano SMD probe printing has been going well since I abandoned the BLTouch and tuned the Z-limit switch within a micron of it’s life. The base is completed, I’m just waiting for a few more of the small arm parts to print and another run of needle holders printed since I think I can get greater accuracy this time around.

The acupuncture needles arrived as desired, with the appropriate copper spool at the top, hopefully making it a little easier to solder to. They’re 40x0.25mm needles, seemingly small enough to accurately poke at the pins on this chip. My main goal is to avoid the need to desolder the PIC16F627A from the PCB and flash it with a PICKIT3 clone using the nano SMD probe kit.

While lazily looking around the internet, I found someone else’s pinout. This saves me having to look up how to wire the exact same kit. Thanks random internet person! I still need to print another few parts, but my SKR 1.4 motherboard showed up, so I started printing a motherboard case, perhaps a bit early since I need some additional wiring and crimping kits to connect it together.

Anyway, I did fully assemble the probe kit, and soldered correctly. I realise now that the probe kit doesn’t form a strong connection which would be required to reprogram these chips. I think the next best thing now would be to monitor the chip with my probe kit, just to see what those pins do at startup and see if there’s anything interesting we can glean from it. For now, I’m shelving this project, this setback was enough to frustrate me into stopping.