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Thank you very much for this series of articles. Please continue with them! One thing that I would love to see eventually is a series of comparisons with the

• kens 6y ago
  I've looked briefly at the 8088. As you know, the 8088 is a modification of the 8086 with an 8-bit bus instead of the 16-bit bus. Here's a quick summary of the differences: Looking at the dies, the 8086 and 8088 are completely identical over most of the die. For the most part, I can look at the 8088 die if something is unclear in my 8086 photo. The biggest difference is the bus control logic, which is entirely different (as you'd expect). This is in the upper-right corner. The 8088 has a 4-byte instruction queue instead of a 6-byte instruction queue, so there's a bit of wasted space in the register file there. The queue registers and control circuitry are slightly different because the 8088 needs to access half of the word at a time. I saw a couple of microcode differences, but I don't know if they are related to 8086 vs 8088 or are bug fixes. Some of the pin driving circuitry is different, as you'd expect, since only 8 pins are used for data. To summarize: is the 8088 a completely redone chip? No. Are they the same chip with a jumper? No. Most parts of the 8086 and the 8088 are the same, but some parts were completely redesigned.