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I have to learn ASM85 for class, but my professor's lecture notes are pretty bad (not a native speaker), so I'm wondering if I could just study the ASM for Intel 8086.

Or if there are good resources for learning ASM85, that would be much appreciated.

Chinguun Erdenebadrakh
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    They are very different. Try a search on "8085 vs. 8086" for explanations such as https://www.geeksforgeeks.org/differences-8085-8086-microprocessor/ – Dave S Jun 13 '20 at 21:57

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8086 is a significantly different ISA. It won't be very helpful to learn it as well, beyond the fact that many of the basic concepts of assembly language are the same across ISAs, just different details.

Once you know assembly better, you can see how 8086 was designed for easy source-level porting from 8080 / 8085 by extending the registers from 8 to 16 bit. https://retrocomputing.stackexchange.com/questions/6500/the-start-of-x86-intel-8080-vs-intel-8086/6501#6501 (8080 and 8085 are essentially binary / asm compatible with each other, but not 8086).

But when you don't know either, just learn the one you need to learn.

8080 is closer to a 1-operand ISA where everything has to use the accumulator, or at least an implicit register implied by the mnemonic. But 8086 is fully a 2-operand ISA with 8 more or less general-purpose 16-bit registers. The addressing modes are also very different from 8080.

Peter Cordes
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