Replies: 3 comments 4 replies
-
|
I would like to do so eventually. It will require some additional research to make it reasonably accurate. Unfortunately, the microcode for the 286 has not been decoded. |
Beta Was this translation helpful? Give feedback.
-
|
how everybody else overcomes it? what about 386? |
Beta Was this translation helpful? Give feedback.
-
|
@darvin They don't emulate the 286 cycle-accurately that's how lol |
Beta Was this translation helpful? Give feedback.
-
Implementing the 286 instruction set is one thing, doing it in an accurate way is another. Does the world need a cycle-accurate 286? maybe not, but it is something that interests me for some reason. |
Beta Was this translation helpful? Give feedback.
-
|
isn't it's impossible to run cycle accurate 286 emulation - because the are no published microcodes? what exactly codes in microprocessors do anyway? which ROM is code for microprocessor? |
Beta Was this translation helpful? Give feedback.
-
|
maybe not impossible but it makes it much more difficult. microcode allows more complicated instructions to be built up from smaller one, each CPU instruction is essentially a small program that runs on the CPU. Sometimes this program is just a set of instructions that execute in order, which is simple to emulate, but sometimes there can be branches or conditions which makes it harder to determine what the program logic is. The microcode ROM is on the CPU die itself. If you are interested in learning more about microcode this is a good blog: |
Beta Was this translation helpful? Give feedback.
-
|
Related:
|
Beta Was this translation helpful? Give feedback.
-
How hard would be to extend emulator to support 80286?
Beta Was this translation helpful? Give feedback.
All reactions