He went even farther, decapping the CPU and reverse engineering its entire workings to understand how each "undocumented" opcode functioned: https://www.pagetab

He went even farther, decapping the CPU and reverse engineering its entire workings to understand how each "undocumented" opcode functioned: https://www.pagetable.com/?p=517 https://www.pagetable.com/?p=517