Fred's blog

承年初『 親手打造 HD 多媒體播放器 』所述，小弟有幸於今年 1/23（六）、1/24（日）、3/27（六）、3/28（日），在台中『靜宜大學應數系』開設嵌入式系統實作課程，課程宗旨欲藉由一步步的實作，揭露嵌入式系統開發細節。本課程嘗試避免提及過於深奧的理論和艱澀的名詞，以玩樂中學習並體驗嵌入式系統相關技術。除了實作外，也略微說明相關基礎知識，如：Compiler、 NEON intrinsics 等。 感謝各界參與，本課程已順利結束，有興趣者可自行下載上課簡報檔： http://people.linux.org.tw/~fred/slides/training/hdplayer.pdf

As you know, I've done Android Eclair porting for Devkit8000 in the past, which is based on Embinux. It's a experimental work for passing time, I have no time to maintain and fix bugs friends reported after that. However, I think it is not good because the result will be getting lost as time goes by. 0xdroid is another Android distribution which is different from Embinux, its developer  Jim Huang(jserv)  who has contacted me a few months ago, and he hope that I can try porting 0xdroid on the Devkit8000. Actually, I am glad to make 0xdroid takes over my work, it is the best result for me. Currently, I've done most works, 0xdroid can run on Devkit8000 with success. And also, My patches have been committed to 0xlab-devel mailing list. Because I have another platform SBC8100 which is also produced by Embest, I've done works on that as well. You can see my patches from 0xlab-devel mailing list, or you can visit my website to download it directly: http://people.lin...

Recently, our team work hard on ARM platform which is TI OMAP 3530, and also it makes us crazy actually. As you know that source code of TI PowerVR driver and SGX is not publicly available, there is no open source solution cause it's difficult to debug graphical stuffs. If you have tried to use Clutter with EGLX Backend, you might get only the blank stage and nothing works correctly. It happened due to X server might still have things in its buffer to render when swap buffers. Here is a patch to solve this problem: http://people.linux.org.tw/~fred/patches/clutter-1.0_1.0.8-wait-for-vsync-before-SwapBuffers.patch

本月 1/23（六）、1/24（日）兩天，小弟將於台中的『靜宜大學應數系』開設嵌入式系統課程。一如課程名稱『 親手打造 HD 多媒體播放器（上） 』，將試圖發揮 TI OMAP 353x 的威力，打造多媒體播放器。近年來『 Beagleboard 』面世，其低廉的價格及強大的硬體效能，在嵌入式系統領域造成不小的影響，使許多人可輕易入手開發板，並在上面做各式各樣的應用。在網路社群中，beagleboard 也因此廣為受歡迎，相關文件齊全，各種技術支援都能輕易取得。 我們將選用 Beagleboard 的複製品『 Devkit8000 』做為硬體平台，硬體規格和設計幾乎完全與 Beagleboard 相同。之所以選用 Devkit8000，除了因為硬體設計和 Beagleboard 一樣之外，其各種接頭支援相當完整，不用再自行焊接，對於軟體開發人員來說，比 Beagleboard 來的方便許多。 此課程總共分上、下兩部份，上半部從嵌入式系統基礎和認識講起，將談及嵌入式系統現況與未來展望、開發環境架設、嵌入式 Linux 基礎架構，適合入門者參加。由於嵌入式系統以實作經驗為重，課程將以實作為主進行，如題『親手打造』一詞，藉自己動手做以增加實務經驗。 註：靜宜大學將提供學生開發板使用，只需帶著玩樂的心前來即可。 活動詳細訊息 活動名稱：嵌入式系統short courses 活動網址： http://www.excellent.pu.edu.tw/news_detail.php?sid=0&id=1366 活動目標： 嵌入式系統開發系統介紹，了解嵌入式系統的現況與未來展望 做中學--學習嵌入式系統的開發環境佈署與建置 活動日期：1/23　09:00-16:00 演講者：于昌永老師、錢逢祥工程師 地點：靜安425 對象：全校師生、育成培育廠商 人數：30人 承辦單位：應用數學系 參考資料： Devkit8000： http://elinux.org/DevKit8000 http://fred-zone.blogspot.com/2009/12/android-eclair-porting-for-devkit8000.html http://fred-zone.blogspot.com/2009/12/ena...

Using Android on Devkit8000, we have problem of getting back to previous screen. The touchscreen can only be used to decide whether you select item or not, so a BACK button would be needed absolutely for Android. Devkit8000 board has four buttons on the corner, we can set one of it as Back functionality. First step, add a option to kernel config file to enable GPIO keyboard device: CONFIG_KEYBOARD_GPIO=y Second step, set USER_KEY as ESC Keycode for back functionality: diff --git a/arch/arm/mach-omap2/board-omap3devkit8000.c b/arch/arm/mach-omap2/board-omap3devkit8000.c index e86d254..ec17311 100644 --- a/arch/arm/mach-omap2/board-omap3devkit8000.c +++ b/arch/arm/mach-omap2/board-omap3devkit8000.c @@ -462,9 +462,11 @@ static struct platform_device leds_gpio = { static struct gpio_keys_button gpio_buttons[] = { { - .code = BTN_EXTRA, +// .code = BTN_EXTRA, + .code = KEY_ESC, .gpio = 26, .desc = "user", + .active_low = 1, .wakeup = 1, }, ...

If you would like to make Android work on Devkit8000, you can follow to patch your kernel which is mentioned in my old article( Android Eclair Porting for Devkit8000 ). After that you might notice the touchscreen doesn't work, it is a ads7846 kernel driver bug from Embinux. So I modified a few lines of code to fix the bug. Here is the patch: http://people.linux.org.tw/~fred/patches/devkit8000-touchscreen-android-kernel.patch

It's not only for fun! Porting Android is a great practice for me as well. Devkit8000 is a clone of OMAP3 Beagle(Beagleboard), so we can found many porting informations of Beagleboard from internet. It's helpful for us, we only need to deal with a few places which are some differences between Devkit8000 and Beagleboard. Google Android Eclair is working well on the Devkit8000 board now after I tried to port it last weekend. Here is the patch: http://people.linux.org.tw/~fred/patches/devkit8000-android-kernel.patch Based on Embinux , I added the Devkit8000 support, which includes: OMAP DSS Driver for display 4.3 inch LCD Panel support (480x272 60Hz) 7 inch LCD Panel support (800x480 60Hz) Touchscreen ADS7846 support Sound Codec (TWL4030) Keypad (TWL4030) Ethernet Device support (DM9000) Kernel Config for Android Compile Kernel with Devkit8000 kernel config: make omap3_devkit8000_android_defconfig make CROSS_COMPILE=arm-linux-gnueabi- uImage Kernel Comman...