A table showing the 5-bit codes that specify registers.

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1. Ken Shirriff (kenshirriff@oldbytes.space)'s status on Saturday, 11-Mar-2023 21:32:57 UTC Ken Shirriff

   in reply to

   Instructions for the 8086 processor specify registers through 3 bits in the opcode or following byte. This is expanded to a 5-bit code to support 16-bit registers (red), 8-bit registers (blue), segment registers (green), and special internal registers.