Open Hardware/Modding: Retro and Small Computing
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Silicon reverse-engineering: the Intel 8086 processor's flag circuitry
The die photo below shows the 8086 microprocessor under a microscope. The metal layer on top of the chip is visible, with the silicon and polysilicon mostly hidden underneath. Around the edges of the die, bond wires connect pads to the chip's 40 external pins. I've labeled the key functional blocks; the ones that are important to this discussion are darker and will be discussed in detail below. The Arithmetic/Logic Unit (ALU, lower left) is split in two. The circuitry for the flags is in the middle, giving it access to the ALU's results for the low byte and the high byte. I've marked each flag latch in red in the diagram below. They appear to be randomly scattered, but there are reasons for this layout.
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Hacking the Geberit Sigma 70 flush plate
After several plumbers, exchanges with Geberit’s technical department, and the expensive replacement of the entire mechanism, I was still getting a failure rate of over 50% for the small flush. I finally managed to decrease this rate to 5% by applying two 8 mm silicone bumpers on the back of the plate. Their locations are indicated by red circles on the picture below: [...]
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Raspberry Pi Weather Station Features Wireless Sensor Nodes
Online weather services are great for providing generic area forecasts, but they don’t provide hyperlocal data specific to your location. [Harald Kreuzer] needed both and built a Raspberry Pi Weather Station that provides weather forecasts for the next 7 days as well as readings from local sensors. The project is completely open source and based on a Raspberry Pi base station which connects to ESP32 based sensor nodes and online services to nicely present the data on a 7″ touch screen display.