- Reverse engineering the ARM1, ancestor of the iPhone’s processor (righto.com)
Almost every smartphone uses a processor based on the ARM1 chip created in 1985. The Visual ARM1 simulator shows what happens inside the ARM1 chip as it runs; the result (below) is fascinating but mysterious. In this article, I reverse engineer key parts of the chip and explain how they work, bridging the gap between the puzzling flashing lines in the simulator and what the chip is actually doing. I describe the overall structure of the chip and then descend to the individual transistors, showing how they are built out of silicon and work together to store and process data. After reading this article, you can look at the chip’s circuits and understand the data they store.
- Lyndon B. Johnson (Wikipedia)
Lyndon Baines Johnson (/ˈlɪndən ˈbeɪnz/; August 27, 1908 – January 22, 1973), often referred to by his initials LBJ, was an American politician who served as the 36th president of the United States from 1963 to 1969. He became president after the assassination of John F. Kennedy, under whom he had served as the 37th vice president from 1961 to 1963. A Democrat from Texas, Johnson also served as a U.S. representative and U.S. senator.