- The Intel 8086 processor (1978) has a complicated instruction set with instructions ranging from one to six bytes long. This raises the question of how the processor knows the length of an instruction.1 The answer is that the 8086 uses an interesting combination of lookup ROMs and microcode to determine how many bytes to use for an instruction. In brief, the ROMs perform enough decoding to figure out if it needs one byte or two. After that, the microcode simply consumes instruction bytes as it needs them. Thus, nothing in the chip explicitly “knows” the length of an instruction. This blog post describes this process in more detail.
instruction length decoding of
- Nashville, Tennessee (Wikipedia)
Nashville is the capital and most populous city in the U.S. state of Tennessee and the county seat of Davidson County. Located in Middle Tennessee, it had a population of 689,447 at the 2020 U.S. census. Nashville is the 21st most populous city in the United States, and the fourth most populous city in the southeastern U.S. Located on the Cumberland River, the city is the center of the Nashville metropolitan area, and is one of the fastest growing in the nation.