Smartphones #1: two bricks in one day

The beginning of the series about smartphones that I experiment on and try to run postmarketOS.

auchan-s6s5in3g:

As it turn out I was able to flash and run recovery made for the different phone with the same SoC, bricking Android at the same time :/. There’s no video but adb works and that alone was enough to make a backup from which I was able to retrieve dts file(see glossary). That file may simplify porting process immensely. Why? With newer Linux kernels (including newest one) I may be able to use generic kernel made for the SoC brand used in this phone (Spreadtrum) and combine it with the dts file to get kernel boot on this device.

sony-taoshan:

This will make a fine addition to my collection, there’s an LineageOS kernel for it which, in theory, should allow for easy porting pmos. Oh naive me. After flashing pmos even kernel didn’t work so I thought about making backup of the whole phone before I hardbrick it, but I needed custom recovery for this. Sadly, as most phones have separate boot and recovery partitions this one does not >:(. I can’t just flash recovery since it would overwrite existing kernel, preventing currently installed system from booting. For each system/kernel I’d have to pack files for recovery mode which would be annoying, so for now I have phone with no working system on it, without backup, waiting for influx of my patience.

glossary:

DTS is a compiled DTB file, also known as  Device tree, that file contains information about all components of the device, such as CPU, GPU, memory, screen, etc. It allows to compile one generic kernel which then reads DTS file and activates needed peripherals instead of compiling specialized kernel for each phone.

fastboot – special mode in smartphones which allows for installation of new firmware, replacing whole partition instead of single files

recovery – special mode in smartphones which allows for installation of new firmware, or updating it without reflashing everything; resetting phone to factory default or making backups

Short follow-up

It is over 2 months since my last entry, so I made this brief summary and try to write more often (yeah, suuure):

  • Retro Day on my faculty, 8-bit edition, there was an opportunity to touch and code in BASIC for Commodore 64, ZX Spectrum+, Atari 65XE. there were some game consoles too
  • I definitely need to  make more documentation, photos mainly 🙁
  • I was in Bytom in HML, HMF ad HDMI labs, it’s incredible how much space all of it takes and how precise readings you can get, for mocap it’s less than 1mm

Hardware:

  • I looked like princess with OCZ NIA,  now I know why this kind of game controller didn’t catch on (BECAUSE IT DOESN’T WORK!!!111)
    • There’s a chance it could work if the device is properly grounded or I change some options in software, need to check that
  • I lost lots of time to disassemble VCR , unsolder modulator, search to what it was connected, in the end I didn’t find anything interesting sine I lack datasheets to make anything useful out of old TV modulator, so I assembled it back together :/

Entertainment:

  • “dsp_enhance_stereo 1” in TF2 wins Command of the Year award for me
  • Saints Row 2 on gamepad is way different than on keyboard+mouse, I remember this game was fun but now it went to overdrive 😀

 

Retro Day:

Find a path from point A to point B, hard version:

From left to right: ZX Spectrum Vega, place for Uzebox (DIY console, not on the photo), Atari Flashback 8 and C64 mini: