Delete comment from: Ken Shirriff's blog
I don't understand how the PLA works. Isn't a single transistor enough to pull the output low? If so, where does the AND function come from? Is the pull up resistor sized such that it takes N transistors to overpower it? But I cannot see how you can get a reliable high voltage with 9 transistors and a reliable low with 10 transistors (assuming the worst case of matching b11111111 with CLOCK and FETCH).
Oct 14, 2020, 12:28:06 PM
Posted to HP Nanoprocessor part II: Reverse-engineering the circuits from the masks