- Counting bits in hardware: reverse engineering the silicon in the ARM1 processor (righto.com)
How can you count bits in hardware? In this article, I reverse-engineer the circuit used by the ARM1 processor to count the number of set bits in a 16-bit field, showing how individual transistors form multiplexers, which are combined into adders, and finally form the bit counter. The ARM1 is the ancestor of the processor in most cell phones, so you may have a descendent of this circuit in your pocket.
- Rockhounding Saddle Mountain Washington For Petrified Wood (rockseeker.com)
Saddle Mountain, a remote and rocky ridge located in central Washington. These hills rise to 2700 feet and offer stunning views of the desert landscape and the Columbia River below. But that’s not all – the fossilized wood on these rugged hills contains a record of the area’s geological history. Petrified or opalized wood is the official gemstone of Washington, and Saddle Mountain is a treasure trove for rock enthusiasts who love agatized wood.