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+---
+name: test-xteink-firmware
+description: "Build and interactively test Xteink ESP32-C3 firmware in the native emulator. Use when validating firmware UI, buttons, screenshots, serial output, SD behavior, or networking."
+---
+
+# Test Xteink Firmware
+
+## Overview
+
+Build firmware for an Xteink device, boot it in the native emulator, and validate behavior through serial logs, physical controls, screenshots, SD state, and network access.
+
+## Prerequisites
+
+Point `XTEINK_QEMU_REPO` at a prepared QEMU checkout containing `dist/qemu-native`:
+
+```sh
+export XTEINK_QEMU_REPO=${XTEINK_QEMU_REPO:-../qemu}
+export XTEINK_EMU_STATE=/tmp/xteink-firmware-$UID
+export XTEINK_EMU_SD=/tmp/xteink-firmware-$UID.img
+```
+
+The emulator exits with setup instructions when its native QEMU distribution is missing.
+
+## Workflow
+
+1. Inspect the firmware project and use its documented build command. Locate the resulting ESP32-C3 application binary; for PlatformIO this is commonly:
+
+   ```sh
+   pio run
+   export XTEINK_FIRMWARE=.pio/build/default/firmware.bin
+   ```
+
+2. Create a persistent FAT32 SD image once, unless the test requires a fresh card:
+
+   ```sh
+   truncate -s 64M "$XTEINK_EMU_SD"
+   mkfs.fat -F 32 "$XTEINK_EMU_SD"
+   ```
+
+3. Start a clean emulator process while preserving SD contents:
+
+   ```sh
+   uv run --script "$XTEINK_QEMU_REPO/scripts/xteink-emu.py" stop \
+     --state-dir "$XTEINK_EMU_STATE" || true
+   uv run --script "$XTEINK_QEMU_REPO/scripts/xteink-emu.py" start \
+     --state-dir "$XTEINK_EMU_STATE" \
+     --firmware "$XTEINK_FIRMWARE" \
+     --sdcard "$XTEINK_EMU_SD"
+   ```
+
+   `start` simulates a two-second power-button hold for cold boot. Override `--power-hold-ms` when testing power behavior.
+
+4. Observe serial behavior with either a persistent regex cursor or the raw log:
+
+   ```sh
+   uv run --script "$XTEINK_QEMU_REPO/scripts/xteink-emu.py" wait \
+     --state-dir "$XTEINK_EMU_STATE" --timeout 30 --match 'pattern'
+   tail -f "$XTEINK_EMU_STATE/serial.log"
+   ```
+
+5. Drive the physical controls:
+
+   ```sh
+   uv run --script "$XTEINK_QEMU_REPO/scripts/xteink-emu.py" button \
+     --state-dir "$XTEINK_EMU_STATE" bottom-2
+   uv run --script "$XTEINK_QEMU_REPO/scripts/xteink-emu.py" button \
+     --state-dir "$XTEINK_EMU_STATE" power --down
+   uv run --script "$XTEINK_QEMU_REPO/scripts/xteink-emu.py" button \
+     --state-dir "$XTEINK_EMU_STATE" power --up
+   ```
+
+   Available buttons are `left`, `right`, `bottom-1` through `bottom-4`, and `power`. Use the labels rendered by the current screen as the authoritative mapping. Allow the e-ink panel to refresh after state-changing input.
+
+6. Capture and inspect the screen after meaningful transitions:
+
+   ```sh
+   uv run --script "$XTEINK_QEMU_REPO/scripts/xteink-emu.py" screenshot \
+     --state-dir "$XTEINK_EMU_STATE" --output /tmp/xteink-screen.png
+   ```
+
+7. Enter text when the firmware's on-screen keyboard is focused:
+
+   ```sh
+   uv run --script "$XTEINK_QEMU_REPO/scripts/xteink-type-keyboard.py" \
+     "$XTEINK_EMU_STATE" normal 'Example'
+   uv run --script "$XTEINK_QEMU_REPO/scripts/xteink-type-keyboard.py" \
+     "$XTEINK_EMU_STATE" url 'https://example.com'
+   ```
+
+8. For network tests, connect the firmware to the single open Wi-Fi network named `qemu`, then validate the feature's observable result.
+
+## Diagnose Failures
+
+- Firmware serial output: `$XTEINK_EMU_STATE/serial.log`
+- Emulator output: `$XTEINK_EMU_STATE/qemu.log`
+- Assembled flash image: `$XTEINK_EMU_STATE/flash.bin`
+- Resolve crash addresses against the exact ELF produced with the tested binary, using the project's RISC-V `addr2line` tool.
+- Preserve the SD image when reproducing persistence bugs; replace it when testing first-boot behavior.
+
+## Cleanup
+
+```sh
+uv run --script "$XTEINK_QEMU_REPO/scripts/xteink-emu.py" stop \
+  --state-dir "$XTEINK_EMU_STATE"
+```