Tone2 Pro - Firmware v1.2 for XMOS & MCU

Summary: we've fixed issues with the Audio Filter and Noise Floor measurements.

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Who Needs This:

• You have a Batch 1 or 2 Tone2 Pro

• Your serial number starts with 0C... or 11...

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Summary:

We’re now ready to release the v1.2 XMOS firmware and New MCU firmware for your Tone2 Pro. These two files when used in combination, will fix several issues such as the audio filters, and the high-noise floor at 44.1kHz and 48kHz respectively.

Noise Floor at 44.1kHz (Blue) and 48kHz (Pink)

FFT Spectrum of White Noise (Various Audio Filters)

If you have a batch 3 or later Tone2 Pro device, you do not need to perform this upgrade.

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Changelog:

• New MCU Firmware

  • Fixed Audio Filters (White Noise)

  • Fixed 44.1kHz and 48kHz (THD+N)

  • Fixed Mono Signal (Low Probability)

  • Enabled MCU upgrade via USB DFU
    

• XMOS Firmware v1.2

  • Enabled MCU upgrade via USB DFU

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Downloads:

• XMOS:

  • XMOS DFU Tool

  • XMOS v1.2 Firmware
    

• MCU:

  • MCU DFU Tool

  • New MCU Firmware

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Hardware Tool:

Please note that to perform the MCU upgrade, you’ll need an ST-Link v2 hardware tool. However after this update, subsequent MCU updates can be done over the USB-C port. We will include a link in Khadas Shop (you must provide proof-of-purchase of your Tone2 Pro) for you to get a free ST-Link v2 hardware tool.

This hardware device plugs into your computer’s USB port, and pokes into the Tone2 Pro’s GPIO pins on the underside. Refer to the MCU update guide below for usage instructions.

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Updating the XMOS:

To update the XMOS firmware to v1.2, follow this YouTube video as per normal.

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Updating the MCU:

1. Connect the Tone2 Pro to your PC.

2. Install the ST-Link v2 software tool (run as administrator).

3. Download and unpack the New MCU Firmware.

4. Open the MCU upgrade tool.

5. Configure the tool.

6. Connect the tool to your PC's USB port.

7. Peel away a portion of the rubber foot below the “tone” branding.

8. Insert the pins into your Tone2 Pro, lifting up by 1mm to avoid contact with the metal shell.

9. Apply lateral (side) pressure to ensure good contact with the gold pads inside Tone2 Pro.

10. Open the MCU Firmware .hex file.

11. Press the flash button.

12. Reconnect your Tone2 Pro.

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Linux / Mac OS Automated MCU & XMOS Upgrade Scripts:

Open a Terminal app and copy and paste either of these commands, internet access is required, sudo is not required.

Update MCU:

/bin/bash -c "$(curl -fsSL https://dl.khadas.com/Firmware/Tone2/upgrade_mcu.sh)"

Update XMOS:

/bin/bash -c "$(curl -fsSL https://dl.khadas.com/Firmware/Tone2/upgrade_dfu.sh)"

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If you need more technical help beyond this blog post, please visit the v1.2 firmware discussion over at Khadas Forum.

Warmly,

Khadas Team