Crate psx_rt 

PS1 bare-metal runtime.

Provides the _start entry point that the PSX-EXE loader jumps to, a panic handler, direct i-cache control, a BIOS TTY debug trampoline, and optional heap initialisation. Homebrew crates depend on this crate to get a working main() environment without thinking about linker symbols or cache-flushing.

Entry sequence

1. The loader (our emulator or the real BIOS) copies the EXE payload to LOAD_ADDR and jumps to _start.
2. _start zeroes the .bss section using the linker-defined __bss_start / __bss_end symbols.
3. With the alloc feature, the bump allocator is seeded from __heap_start..__heap_end.
4. main() is called. When it returns, we halt.

Modules

bios

The runtime’s one remaining BIOS entry point: TTY putchar.

cache

Instruction-cache invalidation, done directly on the hardware.

critical_section

Critical sections: run code with CPU interrupts masked.

heap

Bump allocator gated behind the alloc feature.

interrupts

Minimal interrupt support used by engine-level clocks.

present

VBlank-kicked presentation: a one-frame-deep queue between the CPU and the GPU. Built with the present-queue feature.

scratchpad

The CPU scratchpad, and running code with its stack there.

tty

TTY output for debug printing.

Structs

Peripherals

Every shared-state peripheral token, handed out once.

Functions

_start^⚠

Entry point the PSX-EXE loader jumps to.

assert_stack_headroom

Trap (loudly, via TTY) if the live stack pointer has descended into the static data region.

halt

Infinite loop with no useful side effects. Used after main() returns or from panic / reset paths.