[noone_youknow]

Nice work! Looks like most of the basics are covered, and meanwhile in my current kernel the RISC-V entrypoint is >700 lines (of C) just to get to the arch-independent entrypoint!

I was just looking around for your input/output code, I don’t know zig but I expected to find putChar in kernel.zig based on the import in common.zig, but I don’t see it, should I be looking somewhere else? I didn’t see any simple command line processing either as mentioned in the README?

Mostly just looking around since your README mentioned VGA (and you seem to have a BIOS boot) which struck me as interesting on a RISC-V project, I was curious if you were actually using the SBI routines or had actually mapped in a VGA text mode buffer?

[WD-42]

There is a todo in the putchar stub. Looks like it’s not implemented yet.

I have it implemented here in my own roughly 1k line zig kernel: https://github.com/Fingel/aeros-v/blob/ddc6842291e9cf4876729...

[noone_youknow]

Thanks! I see that you’re using the SBI routines, which is what I was expecting here but couldn’t find - the reference to “output text to VGA” in the post made me curious.

I did see the putchar stub in the user.zig but, lacking understanding of zig, wasn’t sure how that could work given common.zig is looking for putChar in kernel.zig as far as I could tell.

I just jumped through a couple of hoops to get zig 0.13 installed and see an error about “root struct of file ‘kernel’ had no member named ‘putchar’” so I guess maybe it’s not implemented here at all.

[WD-42]

I don’t know what output to the VGA means from the OP. I suspect that entire project was vibe coded including the readme. It’s a common first step when writing an OS for x86 but for riscv you don’t use vga to get text output, you go through the UART.

Are you saying you had trouble getting putchar working in my implementation? As far as I know common.console is fully implemented and working. Let me know if something is wrong.

[noone_youknow]

Sorry for the confusion, I was referring to the putchar not being implemented in OPs code, I got yours working right away (nice work btw).

What you mention about VGA being common on x86 was what got me curious, since it’s not a thing on riscv. In my own OS project I’m using a framebuffer to show a graphical terminal on both x86 and riscv64 so I wondered if OP was doing similar or was really using SBI output.