# HDGL C64 — DIAGNOSTIC build (for the NVS 295 "flash blue then reboot")

## What this build does differently

Your symptom — **blue flash, then reboot** — means the kernel reached the C64
face (the framebuffer fix worked; blue = it drew to the right screen) and then
hit a **CPU exception** that, unhandled, cascaded to a triple fault and rebooted
the machine.

This build **catches CPU exceptions and FREEZES on a solid colour instead of
rebooting**, so we can see WHICH fault it is. The colour is the diagnosis:

- **RED**     = General Protection fault (0x0D) — bad memory/segment access
- **MAGENTA** = Page fault (0x0E)              — touched unmapped memory
- **YELLOW**  = Invalid opcode (0x06)          — CPU hit an instruction it can't run
- **GREEN**   = Divide by zero (0x00)
- **WHITE**   = some other exception

## What I need from you

1. Rufus this ISO to USB (DD Image mode), boot the NVS 295 machine from it.
2. It will either:
   - **stay on the C64 face** (READY.) — then the exception was intermittent /
     fixed, tell me and we proceed; or
   - **freeze on a solid colour** — **tell me the colour.** That single fact
     tells me exactly what's faulting on your hardware, and I fix that.

No more reboot loop — it will hold the colour so you can read it.
