AIGO EROS Q / EROS K
Also sold as:
- AGPTek H3 (EROS K)
- HIFI WALKER H2 (EROS Q)
- Surfans F20 (EROS K)
NOTE: The EROS Qii uses a very different internal platform internally, and is *not* supported.
NOTE: Hifiwalker H2 units which ship with v1.3 firmware are not compatible with v1.0-v1.2 firmware (and vice versa). In general, it appears that original firmware is no longer compatible between brands or between original firmware versions. There is a hardware change which started with Surfans F20 firmware 2.7 (and later) and HifiWalker H2 firmware 1.4 (and later), so these certainly are not compatible with original firmware versions prior to the hardware change. The changes are listed below.
EROS Q/HIFI WALKER H2: 90x55x15mm, 152g
EROS K/AGPTek H3/Surfans F20: 94x57x15mm, 111g
Hardware summary
Original Configuration
Hifiwalker units prior to version 1.4 and Surfans units prior to 2.7.
| Component |
Model |
Notes |
| SoC |
X1000 |
1.0GHz MIPS XBurst with 32MB of SIP LPDDR RAM |
| PMU |
AXP192 |
I2C PMU |
| DAC |
TI PCM 5102A |
I2S |
| NAND |
ATO25D1GA 1Gb |
Newer players may use alternate chips |
| Display |
320x240 2" |
|
| Battery |
Li-Ion 3.7v 1300mAh |
|
Other hardware notes:
- Headphone amp: MAX97220
- Stereo switch: ISL54405IRUZ-T
- Bluetooth module: unknown
- micro USB
- The PCM5102A DAC does not have hardware volume scaling.
The Line Out volume can be set by the Maximum Volume setting. Some notes:
- Line Out level at 0 dB in Rockbox seems to be about 6.2 dBV
- For "consumer level" line out, try setting to -16 dB. (-10dBV)
- For "pro level" line out, try setting to -4 dB. (+4dBu -> ~1.8dBV)
The signal flow appears to be something like:
DAC \--> HP Amp --> Stereo Switch --> HP OUT
\-> LO OUT
Hardware disassembly was not necessary to complete this hosted port. Other than Bluetooth, all hardware functionality appears to work.
Newer hardware configuration
Surfans units 2.7 and up, and it would appear Hifiwalker 1.4 and up.
| Component |
Model |
Notes |
| DAC |
Sabre ES9018K2M |
I2S |
| Display |
320x240 2" |
ILI9342 |
Other hardware notes:
- Headphone amp: HT97220
- Stereo switch: WSP6580Q
- Bluetooth module: Qualcomm CSR8811
- USBC (!!)
- The ES9018K2M DAC has hardware volume scaling, but I2C does not appear to be connected.
The Line Out volume can be set by the Maximum Volume setting. Line Out levels appear to be lower than the previous device revision. Some notes from testing (01-28-2023) with the Native port:
- At 0dB in Rockbox, levels should be approximately 2.8 dBV
- For "consumer level" line out, try setting to -12 dB. (-10dBV)
- For "pro level" line out, try leaving it at maximum - Our volume scale only goes up to -2dB for compatibility reasons with the original hardware revision, but this should only be ~1dB down. (+4dBu -> ~1.8dBV)
The signal flow seems to be changed to something like:
DAC --> HP Amp --> Stereo Switch --> HP OUT
\---> LO OUT
Hosted Port
This hosted port runs on top of the original linux-based firmware, and was the original port to the device. If in doubt between this and the native port, choose this one. For the hosted port, the correct patched original firmware update file must be installed and the rockbox firmware unzipped onto the SD card.
Rockbox functions very well on these targets, and nightly builds are considered stable for day-to-day use. The only features that are not available in Rockbox are bluetooth and USB-DAC mode. The player can be booted into the original firmware to use these features.
The
RockboxUtility fully supports these players as of version 1.5.0. However, if you wish to install the bootloader manually, follow these instructions:
- Build or download the bootloader
- Obtain a stock firmware image
- Patch the firmware image with the bootloader
- Rename the patched firmware file to update.upt and place it into the root directory of the SD card
- Grab the latest daily build for the player and unzip it into the root directory of the SD card
- Go into the settings menu and select firmware update.
- Upon reboot, select rockbox from the initial menu
Here you can download the current bootloader builds, along with "binary patches" that can be easily applied to stock firmware update images using the 'bspatch' utility:
For convenience, here are pre-patched images:
--
DanaConrad - 23 Feb 2022
Native Port
Note: At the moment, the native port is a little bit more involved to install, so if you're not sure, you probably want the hosted port above.
If installing the Native port, be sure to back up the preexisting bootloader and save it somewhere safe, in case you should want to go back to the hosted port or the original firmware!
There is a native port in addition to the hosted port. This is installed and run without using the linux-based original firmware. For all variants, use the "erosq" option for jztool.
Dual-booting into the Original Firmware is now supported - hold Play while booting or select the "Aigo Player" option from the bootloader menu, which is accessed by holding Volume Up while booting. The Original Firmware's recovery mode exists, but is entirely untested, so it has been disabled for now.
Installing the bootloader is a manual process; see
JztoolInstall. It's really not that hard, but you do have to run a command line command or two.
This native port functions well, but currently has the following issues:
- No Rockbox Utility support - manual installation is required
- Daily builds are not provided - we do however have builds that are updated every commit located at https://build.rockbox.org/data/rockbox-erosqnative.zip
- Under certain circumstances, the left and right channels may reverse when the system changes sample rates. This is believed to be due to increasing the pcm sample size to 24 bits in order to obtain good quality volume scaling. A fix for this issue is not obvious at the moment, but the workaround is simple: set Frequency (Settings --> Playback Settings --> Frequency) to 44.1kHz and leave it there. This appears to prevent the issue entirely. Looks like this may be fixed by this patchset: Gerrit 5166
The following are more minor things that could be tidied up or are "someday" projects:
- USB HID keys are not yet defined
- LCD could potentially work at a higher bit depth
- Bluetooth support - use the OF for this
- USB DAC functionality - use the OF for this
--
DanaConrad - 21 Jul 2022
Copyright © by the contributing authors.
