Listing by their location, left to right, grouped logically: The Zero has much fewer test pads, numbered out of order. PP13 is for the ACT activity/status LED on the Raspberry Pi B+, but I can’t find it on the Pi Zero. Promising? Found a spreadsheet labeling what they are for: Raspberry Bplus / 0 Test Pads, screenshotted here in its entirety: But there are a bunch of exposed pads on the reverse side, labeled with “PP”: And where may this STATUS_LED signal come from? The “reduced schematics” don’t say. The other side, the cathode (negative), connects to the STATUS_LED signal. But unfortunately it connects to power, not to the signal. Measuring the resistor with a multimeter confirms it is 469.9 Ω, within spec. This is somewhat helpful, it reveals the small resistor to the upper left (R20) is 470 Ω, connecting to 3.3 V. Can we solder somewhere else on the board? Refer to the official Raspberry Pi schematics, for the Raspberry Pi Zero revision 1.3: So I tried applying solder to where the LED was, but to no avail. The LEDs still are operational, off the board:īut that doesn’t help us much off the Pi. And a red LED for activity, to contrast with the green LED for power. My plan was to use stranded wire for strain relief, not solid core as in the first laptop. In the previous update to my custom Raspberry Pi Zero-based cardboard laptop, the onboard surface-mount activity LED on the Pi Zero, along with the external LED I soldered on top of it, accidentally lifted off the board.
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