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majke
This is great. So proper 386 on an fpga? How cool is that.
NooneAtAll3
I wonder what exactly stops windows from booting
nand2mario
Probably some protected mode logic bugs. Just need more time to debug through the boot process.
JdeBP
I wonder how the logic worked in the previous version without early start. Was it relying upon the address calculation speed to settle the outputs really quickly? Was it inserting or stretching cycles?
nand2mario
The memory pipeline just starts one cycle later than now. Effective address is calculated during the first cycle of the instruction. The microcode then waits for it to finish with the DLY (delay) micro-op, which releases one cycle later.
rasz
Would this be related to Next Address (NA#) pin on the 386 enabling Address Pipelining?