nora23169 wrote:
BigDumbDinosaur wrote:
nora23169 wrote:
I'm Japanese and I'm looking forward to working with you and having fun developing the 6502.
Welcome. You’ve come to the right place!僕もx86はいらないと思っています丁度意見が合いましたよろしくお願いします。僕がx86いらない理由は自分のosを自作するのにbiosやuefiが難しいしいらないと思ったからですよろしくお願いします。
Translation: I also don't think x86 is necessary. I agree with you, thank you. The reason I don't need x86 is because I don't need BIOS or UEFI because it's difficult to make my own OS.Thank you in advance.
Reply: Egh, to be fair, the x86 carried a lot of weight with it. Even most 6502 systems had a ROM of some sort, even if it wasn't specifically called a BIOS. While I'm not a huge fan of the x86's decision to go with a segmented memory model in real mode; back in the DOS days, writing an OS wasn't significantly more complicated between the two.
In any event, you don't need a huge complicated BIOS to get a 8086, 80286, Z80 running if you know the exact details of the hardware on the system.
Things started really becoming more complicated when protected mode was introduced, and you couldn't just easily jump back and forth between calling the BIOS (which existed only in real mode) from your protected code. (Yes, it could be done, but it was/is a pain to do so)
UEFI came about later after things started rapidly moving to 64-bit long mode; though it was conceived of towards the end of the 32-bit era of the x86.
In some ways UEFI simplifies making an OS; you effectively can generate a PE32 binary that can use the provided services to do some basic loading and discovery in a flat memory model with a set of basic drivers provided by the hardware vendors.
Unfortunately they also added that awful "secure boot" nonsense which just makes it a pain if you want to test on actual hardware and not a virtual machine.