pico9918-core - the library-paced GPU More...
Include dependency graph for gpu_test.c:
Go to the source code of this file.
Macros | |
| #define | PROGRAM_AT 0x2000u |
| #define | RESULT_AT 0x2100u |
| #define | MARKER 0xbeefu |
| #define | DMA_SRC 0x1000u |
| #define | DMA_DST 0x1800u |
Functions | |
| static void | fail (const char *what, unsigned wanted, unsigned got) |
| static void | regWrite (uint8_t reg, uint8_t value) |
| static void | unlock (void) |
| static void | loadProgram (void) |
| static uint16_t | result (void) |
| static void | arm (void) |
| static void | loadDmaProgram (void) |
| static void | dma (uint32_t src, uint32_t dst, uint8_t width, uint8_t height, uint8_t stride, uint8_t params) |
| static void | expect (const char *what, uint32_t at, uint8_t wanted) |
| int | main (void) |
Variables | |
| static int | failures |
Detailed Description
pico9918-core - the library-paced GPU
Copyright (c) 2026 Troy Schrapel
This code is licensed under the MIT license
https://github.com/visrealm/pico9918-core
pico9918_gpu_set_clock's contract, which nothing else covers: a rate makes the library run an armed program from inside the arming write, and zero leaves the GPU to the host.
The first half is what software detecting an F18A depends on. The probe arms a tiny self-modifying program and reads its result back within a handful of host cycles, so a host servicing the GPU once a scanline sees the chip only when a scanline boundary happens to fall in between - a real flaky-detection bug in two emulators.
The last section is the DMA engine, which is here because a program triggering one is the only way to reach it: the ports it answers to are above the address space a host can write.
Definition in file gpu_test.c.
Macro Definition Documentation
◆ PROGRAM_AT
| #define PROGRAM_AT 0x2000u |
Definition at line 29 of file gpu_test.c.
◆ RESULT_AT
| #define RESULT_AT 0x2100u |
Definition at line 30 of file gpu_test.c.
◆ MARKER
| #define MARKER 0xbeefu |
Definition at line 31 of file gpu_test.c.
◆ DMA_SRC
| #define DMA_SRC 0x1000u |
Definition at line 101 of file gpu_test.c.
◆ DMA_DST
| #define DMA_DST 0x1800u |
Definition at line 102 of file gpu_test.c.
Function Documentation
◆ fail()
|
static |
Definition at line 35 of file gpu_test.c.
◆ regWrite()
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static |
Definition at line 41 of file gpu_test.c.
◆ unlock()
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static |
Definition at line 47 of file gpu_test.c.
◆ loadProgram()
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static |
Definition at line 61 of file gpu_test.c.
◆ result()
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static |
Definition at line 72 of file gpu_test.c.
◆ arm()
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static |
Definition at line 78 of file gpu_test.c.
◆ loadDmaProgram()
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static |
Definition at line 93 of file gpu_test.c.
◆ dma()
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static |
Definition at line 106 of file gpu_test.c.
◆ expect()
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static |
Definition at line 128 of file gpu_test.c.
◆ main()
| int main | ( | void | ) |
Definition at line 133 of file gpu_test.c.
Variable Documentation
◆ failures
|
static |
Definition at line 33 of file gpu_test.c.
