Hacker News: Flex247A

New comment by Flex247A in "Running Doom on Our Custom CPU and Going Viral"

Flex247A — Tue, 21 Jul 2026 08:51:10 +0000

Hi, I didn't follow any specific guide on this, but asked ChatGPT about the bare minimum environment needed to run DOOM. From there, I figured out how to execute the instructions using a switch-case and how to make a custom syscall to trigger rendering.

I made a post a while back that details the entire process: https://www.reddit.com/r/EmuDev/comments/1t1or4j/doom_runs_o...

New comment by Flex247A in "Running Doom on Our Custom CPU and Going Viral"

Flex247A — Tue, 21 Jul 2026 07:30:06 +0000

Great work!

This reminded me of a project I built a while back: a RV32IM emulator in C++ that can boot and run DOOM. Initially I implemented only RV32I, and implementing the M extension provided a massive speedup!

If anyone's curious, here's the source code: https://github.com/lalitshankarch/rvcore

New comment by Flex247A in "Show HN: I built a RISC-V emulator that runs DOOM"

Flex247A — Wed, 06 May 2026 13:34:33 +0000

Pretty much yeah

Show HN: I built a RISC-V emulator that runs DOOM

Flex247A — Sun, 03 May 2026 11:57:12 +0000

Demo: https://www.youtube.com/watch?v=f5uygzEmdLw

Hi HN,

I built a RISC-V emulator that implements the RV32IM instruction set and a minimal syscall interface to run DOOM. A few weeks ago, I got my first output with a simple hello world assembly program.

Since then I have been working tirelessly to get DOOM to run.

I needed to figure out how to run C programs first, and came across newlib, which allows the underlying environment to implement the syscall stubs one by one until the programs run.

I have also added ELF loading, but currently only a single `PT_LOAD` segment is supported.

To port DOOM, I used doomgeneric, which was quite convenient to get working once the required stubs were in place.

DOOM renders to a fixed area in memory (0x705FDD = VRAM_START):

  0x7FFFFF  +-------------------------------------+
            |                                     |
            |        QUEUE_SIZE (32 bytes)        |
            |                                     |
  0x7FFFDF  +-------------------------------------+ <-- QUEUE_START
  0x7FFFDE  |          QUEUE_READ_IDX             |
  0x7FFFDD  |          QUEUE_WRITE_IDX            |
            +-------------------------------------+
            |                                     |
            |                                     |
            |       VRAM (1,024,000 bytes)        |
            |                                     |
            |                                     |
  0x705FDD  +-------------------------------------+ <-- STACK_START
            |                Stack                |
            |                  |                  |
            |                  v                  |
            |                                     |
            |                  ^                  |
            |                  |                  |
            |         Program data + Heap         |
            |                                     |
  0x000000  +-------------------------------------+

I made a small linker script so that the entry point of a C program is at _start and virtual address is always 0. That kept the ELF loader code simple.

Inputs are written to the queue by rvcore which are then intercepted by DOOM running inside it.

Comments URL: https://news.ycombinator.com/item?id=47996055

Points: 50

# Comments: 4

Modern Microprocessors – A 90-Minute Guide

Flex247A — Sun, 12 Apr 2026 09:05:29 +0000

Article URL: https://www.lighterra.com/papers/modernmicroprocessors/

Comments URL: https://news.ycombinator.com/item?id=47737499

Points: 188

# Comments: 21

New comment by Flex247A in "GPU-Driven Clustered Forward Renderer"

Flex247A — Tue, 20 May 2025 17:22:50 +0000

Lights in games use real electricity :)

New comment by Flex247A in "Material 3 Expressive"

Flex247A — Fri, 16 May 2025 11:56:12 +0000

Leetcode monkeys with little dev experience will do that.

New comment by Flex247A in "Compressed music might be harmful to the ears"

Flex247A — Fri, 16 May 2025 10:14:02 +0000

By compression they mean dynamic range compression, which loudens softer sounds so they are more audible.

Pop songs for example, are heavily compressed because "compressed" music sounds "better" on cheap external speakers with bad dynamic range. Kinda like increasing the saturation on a cheap TFT panel.

New comment by Flex247A in "Coinbase says hackers bribed staff to steal customer data, demanding $20M ransom"

Flex247A — Fri, 16 May 2025 08:27:19 +0000

Just when it was included in S&P500 :(

Ubuntu 25.10 Plans to Use Sudo-Rs by Default for Memory-Safe, Rust-Based Sudo

Flex247A — Wed, 07 May 2025 10:27:25 +0000

Article URL: https://www.phoronix.com/news/Ubuntu-25.10-sudo-rs-Default

Comments URL: https://news.ycombinator.com/item?id=43914042

Points: 2

# Comments: 1

New comment by Flex247A in "ePub-utils: A Python library and CLI tool for inspecting ePub from the terminal"

Flex247A — Sat, 03 May 2025 17:59:16 +0000

Personal plug: https://github.com/lalitshankarch/Qitab

This is a small EPUB reader I made that uses the system Webview to render EPUB documents!

Show HN: WinMon – A Lightweight Process Monitor for Windows in Rust

Flex247A — Sun, 27 Apr 2025 07:19:34 +0000

Hi guys,

I’ve always liked the Windows Sysinternals tools, so I decided to reimplement pslist as a small learning project. Ended up using the windows-rs crate and I found that very pleasant to use.

While most of the code is inside unsafe blocks, I really liked how the code ended up being!

Comments URL: https://news.ycombinator.com/item?id=43810087

Points: 3

# Comments: 0