Archos Vision 28
Overview
This is the page for the Archos Vision 28
Port Status
Main Features
Firmware & Upgrade
It is possible to unlock the firmware partition by creating a file called
rkusb.tag
at the root of the filesystem, cleanely unmount and rebooting the player.
DO NOT MODIFY any file or your might render your device unusable
Recovery mode
PCB Scans
Components
- RockChip RK2705: SoC from Rockhip, we already have a port for it
- Hinix H27UBG8T2ATR: flash memory
- EM639165: 16MB SDRAM
- RDA 5807: FM tuner chip, we already have a driver for it
- XPT2046: 4-wire resistive touch controller
OF firmware disassembly
- lcd panel driver seems to be ili9340 or very similar. It is connected in 16bit parallel mode. The screen resolution is 240x320.
- DAP utilizes internal dac (no surprise as there is no external codec chip visible on PCB scans)
- PC0 high keeps power supply (as in other rk27xx devices so far)
- There seems to be software SPI implementation where PC5 = clk, PC4 = mosi, PC3 = miso. PC2 is PENIRQ and PC6 might be related but unclear. It appears that CS might be held low all the time. It looks like interface to XPT2046 configured in single ended mode 8bit resolution. The battery input of the XPT does not seem to be used.
- PC7 is set low at the very beginning and judging from the call placement it is codec related
- power button is routed to PC1, hold is detected via the ADC channel 1.
- sd detect might be routed to ADC channel 2
Copyright © by the contributing authors.