Erasing SPI NAND Flash

This guide explains how to erase the SPI NAND flash memory on Luckfox Lyra boards that include onboard flash storage.

Critical Warning: Data Loss

Erasing SPI NAND will permanently delete ALL data stored on the NAND flash. This action cannot be undone. Ensure you have backups of any important data before proceeding.

Why Erase SPI NAND?

The Luckfox Lyra boot process prioritizes SPI NAND flash over SD cards. If your board has SPI NAND with existing firmware:

• The board will boot from NAND instead of your Calculinux SD card
• Your SD card will be ignored even if properly flashed
• You must erase the NAND to enable SD card booting

Which Boards Have SPI NAND?

Board Model	SPI NAND	Notes
Luckfox Lyra (Base)	❌ No	SD card only
Luckfox Lyra B	✅ Yes	256MB SPI NAND
Luckfox Lyra Plus	✅ Yes	256MB SPI NAND
Luckfox Lyra Ultra/Ultra W	N/A	Uses eMMC, not NAND
Luckfox Lyra Zero W	Varies	Check your specific model
Luckfox Lyra Pi	Varies	Check your specific model

Checking If You Have SPI NAND

Visual Inspection: - Look for an additional chip on the board labeled "SPI NAND" or similar - Check your purchase order/product specifications

Check Product Documentation: - Refer to the Luckfox Lyra documentation for your specific model

Erasure Methods

Method 1: Windows - RKDevTool (Recommended)

This is the easiest and most reliable method for most users.

Prerequisites

• Windows PC
• USB Type-A to Type-C cable (data-capable)
• Luckfox Lyra board with SPI NAND

Step 1: Download Required Tools

1. RK Driver Assistant: Download v5.13
2. RKDevTool: Download v3.31
3. Luckfox Firmware (any official image): Download from Luckfox

Step 2: Install Drivers

1. Extract the RK Driver Assistant ZIP file
2. Run DriverInstall.exe
3. Click "Install Driver"
4. Restart your computer after installation completes

Step 3: Enter Loader Mode

1. Extract and open RKDevTool
2. Method A - Using BOOT button:
3. Disconnect the Luckfox Lyra from USB
4. Hold down the BOOT button on the board
5. While holding BOOT, connect the USB cable to your PC

6. Wait 2-3 seconds, then release the BOOT button

7. Method B - Using RESET button:

8. With the board connected via USB
9. Hold down RESET button
10. While holding RESET, press and hold BOOT button
11. Release RESET, wait 2 seconds

12. Release BOOT

13. RKDevTool should display: Found One LOADER Device

Troubleshooting Device Detection

If the device is not detected, check Windows Device Manager:

• Correct (Loader Mode): Should show "Rockusb Device" under "Universal Serial Bus controllers"
• Wrong: Shows as "ADB Interface" or other device

If not detected properly, try a different USB cable or USB port.

Step 4: Erase the NAND Flash

1. In RKDevTool, click the "Advanced Function" tab (高级功能)
2. Click "Erase Flash" button
3. Wait for the process to complete
4. Tool will display: "Erase Flash Success"

Alternatively, you can erase by flashing a minimal firmware:

1. Click the "Firmware" tab
2. Click the folder icon and select the downloaded firmware update.img
3. Click "Upgrade" button
4. Wait for completion: "Download Successful"

Step 5: Verify Erasure

1. Disconnect the USB cable
2. Insert your Calculinux SD card
3. Power on the device
4. The device should now boot from the SD card

Method 2: Linux (x86_64 Platform)

This method uses command-line tools on Linux.

Prerequisites

• Linux PC (tested on Ubuntu 22.04)
• Luckfox SDK or upgrade_tool
• USB Type-A to Type-C cable

Step 1: Download Tools

Download the Luckfox SDK which includes the flashing tools: - Luckfox SDK Setup Guide

Or download standalone upgrade_tool: - Available in the SDK under tools/linux/Linux_Upgrade_Tool/

Step 2: Enter Loader Mode

1. Hold the BOOT button while connecting the board to your PC
2. Verify detection with lsusb:

lsusb | grep Rockchip

You should see output indicating Loader mode:

Bus 001 Device 007: ID 2207:350f Fuzhou Rockchip Electronics Company

Step 3: Erase Using rkflash.sh

If you have the full SDK:

cd /path/to/luckfox-sdk
sudo ./rkflash.sh erase

Step 4: Verify

# Check the flash is erased
sudo ./rkflash.sh query

Method 3: MaskRom Mode (Advanced/Recovery)

Use this method only if Loader Mode fails or the device is in an unrecoverable state.

Advanced Users Only

MaskRom mode requires physical hardware manipulation and should only be used when Loader mode fails.

Entering MaskRom Mode

1. Locate the Flash Chip: Find the SPI NAND flash chip on your board
2. Identify GND Pin: Locate a ground pin near the flash chip
3. Short Circuit Method:
4. Disconnect power from the board
5. Use tweezers or a wire to short FSPI_CLK pin to GND
6. While keeping the short, connect USB cable
7. RKDevTool should display: Found One MASKROM Device
8. Remove the short circuit once detected

1. Erase in MaskRom:
2. Use RKDevTool "Erase Flash" function
3. Or flash a minimal firmware image

Method 4: Linux on the Device (Not Yet Documented)

Method Not Available

Methods for erasing SPI NAND directly from Linux running on the Luckfox Lyra (without external flashing tools) are not yet documented or tested.

This would theoretically be possible using mtd-utils and /dev/mtdX devices, but specific procedures for Calculinux have not been established.

After Erasing

Once the SPI NAND is erased:

1. Insert SD Card: Insert your Calculinux SD card
2. Power On: Connect power or USB
3. Boot: The device should now boot from the SD card
4. Verify: Check that Calculinux boots successfully

Common Issues

Issue: Board Still Boots from NAND

Symptoms: SD card is ignored, old firmware still runs

Solutions: - Verify the erase completed successfully - Try the erase process again - Try MaskRom mode instead of Loader mode - Check that your SD card is properly flashed

Issue: Cannot Enter Loader Mode

Symptoms: RKDevTool doesn't detect device

Solutions: - Try different USB cable (must be data-capable) - Try different USB port - Check Device Manager for driver issues - Reinstall RK Driver Assistant - Try MaskRom mode

Issue: Erase Fails Midway

Symptoms: Erase process errors or hangs

Solutions: - Disconnect and retry - Try using MaskRom mode - Ensure stable USB connection - Check power supply is adequate

Issue: Device Won't Boot After Erase

Symptoms: No boot after erasing NAND

This is expected behavior! With NAND erased and no SD card: - Insert your Calculinux SD card - Power on the device - It should boot from SD card

Recovery Options

If you need to restore the original Luckfox firmware to NAND:

1. Download the official Luckfox firmware for your board model
2. Follow the official flashing guide
3. Flash the firmware to SPI NAND using RKDevTool

Additional Resources

• Official Luckfox Flashing Guide: wiki.luckfox.com/Luckfox-Lyra/Image-flashing
• Luckfox Forum: forums.luckfox.com
• RK Driver Downloads: Luckfox Tools

Questions?

If you encounter issues not covered here:

1. Check the Boot Problems troubleshooting guide
2. Ask in the Calculinux Forum
3. Refer to Luckfox Official Documentation
4. Open a GitHub Issue

---

Remember: Erasing SPI NAND is a one-way operation. Make sure you understand the implications before proceeding.