About ClearEvo.com

Hello, I’m Kasidit Yusuf - founder of ClearEvo.com. I started ClearEvo.com back in early 2005 - now it serves to host my personal interest/hobby projects and blog. My brother, Adeeb Yusuf, helps do the support and assembly/delivery operations of EcoDroidLink Bluetooth Acess Point.

About Kasidit Yusuf

I’m a ‘Wireless Protocol Software Engineer’ from Thailand. I’ve been developing software related to wireless protocols since 2004, and commercial mobile network test and measurement software since 2006. Currently my work focuses on development of low-level software for radio-chip access and decoding of GSM, WCDMA (3G) and LTE (4G) radio parameters and Layer-3 messages on Android - for the AZENQOS - AZQ Android Network Testing Solution product/Tools under “Freewill FX Company Limited” in Bangkok, Thailand.

My Software Development Experience:

  • Developed ‘azm_db_merge’: https://github.com/freewillfx-azenqos/azm_db_merge
  • My other github projects: https://github.com/ykasidit
  • Developed the main software engine for access and decoding of low-level/deep radio parameters/measurements and Layer-3 messages used in the AZQ Android Radio Network Testing Solution:
    • Developed advanced radio-interface locking features: LTE PCI Cell Locking, LTE EARFCN Locking, LTE Band Locking, WCDMA Dedicated-Mode PSC Locking (disabling Measurement Reports), WCDMA UARFCN Locking, R99 Force, GPRS Force (disabling EDGE), etc - without needing to restart/reboot (power-cycle) the phone for most models.
    • Developed software decoders for GSM Layer-3 Messages: RR, CC, MM, GMM, SM protocols (3GPP 44.018 24.007, 24.008, etc).
    • Developed software decoders for WCDMA Layer-3 Messages: WCDMA RRC (3GPP 25.331) - a big “THANK YOU” to asn1c.
      • Coded the “assembling” of the SysInfo “Segments” as they come over the air - through Qualcomm L3 packets.
    • Developed device specific (radio chipset) methods on Android to digitally play wav sound to telephony voice uplink and also record on downlink of the receiving phone - totally in Android - no need for a notebook PCs to record via its soundcards.
    • Most of the above are developed in pure C programming language - for Android NDK, GNU/Linux testing engine and also Windows DLLs for the AZQ Replay software.
    • Some old code for GSM RR/CC/MM decoding was in C++ (with wxWidgets core and also legacy Symbian C++) - before I learned that pure C was much more suitable for my tasks and preference and switched to C fully.
    • Experience with Qualcomm protocols/formats, Diagnostic packets, modem command/reponse protocols and related Android Linux kernel drivers.
    • Experience with Qualcomm tools: QXDM, QCAT, etc.
    • Experience with LTE, VoLTE, LTE Carrier Aggregation, WCDMA and GSM L3 signalling protocols and parameters.
  • Digitally recoding Telephony Downlink audio, digitally playing wav audio to Telephony Uplink on Qualcomm MSM, MDM and Exynos+MDM (S6 HK) Android phones - for audio quality sample recording (on GSM/WCDMA and VoLTE).

  • VoLTE SIP full decrypted (behind IPSec) message access and RTP, RTCP packet statistics - on some Android VoLTE phone models - requires kernel and system modificaitons.

  • Android enterprise software/kernel modifications that can directly read/write modem settings, and directly read/write modem command pipes without going through Android RIL.

  • Enterprise Android ‘root’ app firmware development - also disbling SELinux and other security features that can block certain engineering access. The kernel modifications that allow ‘root’ access to only certain enterprise apps. Customer simply flashes the ‘custom firmware’ and installs the enterprise app that requires root. Phone is not ‘rooted’ - root checkers would show so. (Nexus 5X, Samsung S6 HK, Samsung S5, Note 4/Edge, Google/LG Nexus 5, etc).

  • Some Android Linux Kernel Driver pathes for ARM (Qualcomm MSM) targets - worked on a driver improvement to better handle high speed packet logging when running on multi-cores like Google Nexus 4 (2013)
    • The stock kernel’s char driver gets blocked/clogged/locked after a few minutes of HSPA+ logging on the “Nexus 4” - 4.2.2
    • Successfully researched/debugged and developed a solutuion/patch - no more blockage even after 13+ hours of high-speed logging. Sent the msm kernel driver improvement patches to Qualcomm cdmatech support too (but most of the problems were already fixed in a different and better manner in newer kernel drivers that were under development at the same time).
  • Happy to be one of the world’s 29 winners of Symbian’s global “Because of the Code” competition in 2007.
    • That was a world-wide competition - send 100 lines of Symbian C++ code and let the expert judges compare and choose a few…
  • Graduated in Computer Science (BSc) from Kasetsart University, Thailand.

  • Developed a C++ implementation of Bluetooth protocols L2CAP, SDP, RFCOMM and OBEX (Acedemic “Computer Science” Project during BSc studies at Kasetsard University) to send files via Bluetooth:
  • A Winner of Thailand Java Contest 2003. In category “Personal Applications” - the J2ME project “Bangkok Bus Pathfinder” developed with my colleague Anon Sutichairatana. Developed a file indexing/storage system that stored the whole database of all Bangkok bus routes (bus number “109” for example) and the “places”/”main stations” that it pased into a searchable database for the tiny RAM (about 50K if I remember correctly) available in the Siemens SL45 - it can also search (even connecting routes) for what bus take to get from “start” to “destination” by querying a Java-Servlet via GPRS.

Contact me: Please email <ykasidit[AT]gmail.com>

How I work

Nowadays, I mostly code pure C - in GNU Emacs! I even write this website in Emacs - using nanoc (in Markdown) and git to manage/upload the site to server. I work mainly using Ubuntu…


Other interests

Raspberry Pi

Developed a solution to make a Raspberry Pi computer work as a “Bluetooth Network Access Point” for Android”. Developed the “Bluetooth NAP” management software for BlueZ, mixed into a solution on Archlinux ARM - please visit the EcoDroidLink - Android Reverse tethering via Bluetooth page. An EcoDroidLink unit is used in my house and kept always-on (24/7) for many moths and still running strong - providing low-power Bluetooth internet to my Sony Xperia Android phone to enjoy browsing classic Mercedes diesel videos and also watching renewable energy videos on Youtube.

Biodiesel

  • Successfully made about 50 litres of Biodiesel from Waste Vegetable Oil and used it in my w123 Mercedes Benz 300D - Naturally Aspirated - long restoration endeavour and pride too!

  • Initially used the base transesterification method, then used the Acid-Base method from JourneyToForever - Aleks Kac formula but discontiued as now (2014-2015) ‘used vegetable oil’ is almost or even more expensive than petro-diesel here in Thailand!

  • Exploring, little by little in my spare time, other methods to work with low-quality high FFA feedstocks.


This ClearEvo.com website is powered by Debian GNU/Linux, running lighttpd, generated using nanoc on Ubuntu.Using the web-template MDL skin - Apache License, Version 2.0 - from getmdl.io