pico2w_csync_step1 — Progressive CSync on Raspberry Pi Pico 2 W (Step 1)

This is a step‑1 port of your composite‑sync PIO logic to a standalone Pico SDK application:

• No Linux / DRM / RP1‑DPI dependencies
• Inputs: HSYNC, VSYNC on user‑selectable GPIOs
• Output: CSYNC on a user‑selectable GPIO
• Implements the progressive‐scan variant (interlaced/TV style will be Step 2)

Pin defaults (edit in main.c)

PIN_HSYNC = 2
PIN_VSYNC = 3
PIN_CSYNC = 4

Change INVERT_* flags if your incoming HSYNC/VSYNC are active‑low.

Timing

Set PIXEL_CLK_HZ, H_TOTAL, H_SYNC_START, H_SYNC_END. The program computes the extend constant tc to match the original logic.

Build

export PICO_SDK_PATH=/path/to/pico-sdk
mkdir build && cd build
cmake ..
make -j

Flash the resulting pico2w_csync_step1.uf2 to your Pico 2/W.

Notes

• Output is 3.3V TTL. For SCART/75Ω you need proper resistor network/AC coupling.
• This step does progressive only. Next steps will add interlaced/TV‑style paths and runtime configuration.