Follow this guide carefully to successfully re-flash your PolarStar FCU firmware.

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🔹 What You Will Need

• Firmware File – Available for download at PolarStar Downloads.

   

• AVR Programmer – We recommend the AVRISP MkII, the ICE Programmer, or a more affordable option:

  • • Microchip ICE Programmer (Official Option)

    • Amazon Programmer – Pocket AVR Programmer

• Programming Software – Download Microchip Studio (Free)
  Download Microchip Studio.
• Pogo Pin Adapter (Required for stable connection)
  Get it on Amazon.

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🔹 Step-by-Step Re-Flash Guide

1️⃣ Open Microchip Studio & Set Up Programming

• Open Microchip Studio and go to Tools → Device Programming.
• Or use the shortcut Ctrl + Shift + P.

2️⃣ Select Programmer & Chip

• In the Tool dropdown, select your AVR Programmer.
• In the Device dropdown, select ATMega169A, then click Apply.

3️⃣ Configure Interface Settings

• Under "Interface Settings", set the clock to 125 kHz.

4️⃣ Load Firmware File

• Go to the "Production File" tab and select the .elf firmware file you downloaded.

5️⃣ Enable These Checkboxes

✅ Flash
✅ EEPROM
✅ Verify Device ID
✅ Erase Memory Before Programming
✅ Verify Programmed Content
❌ DO NOT select "Fuses and Lock Bits"

6️⃣ Power the FCU & Verify Connection

• Plug in a battery to power the FCU.
• Use the pogo pin adapter to connect to the board.
• Click “Read” to verify the connection.

7️⃣ Flash the Firmware

• If the connection is good, click “Program”.
• Hold the pogo adapter steady until the status shows "Programming Complete".

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🔹 Final Steps

✅ Your FCU is now re-flashed!
If you run into any issues, reach out for support in our Discord or via PolarStar customer service.

📌 Join Our Discord for Support → Click Here