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This page mainly summarizes solutions to some main problems during the development of Embest DevKit8500. Hope it would give you some help. Please find the FAQ in Chinese from DevKit8500_FAQ.

Hardware problem

Why my new bought 7-inch LCD has no display when power on the board?

Answer: This is a very normal problem. Embest default delivery is preloaded with 4.3-inch LCD image. User needs to change the image for 7-inch LCD. Please follow the document "Devkit8500 Quick User Manual.pdf" included in product DVD.

Why the touch screen could not be used when getting into WinCE system?

Answer: When getting into WinCE system, the LCD displays as below, there is no response if using finger to click the center cross. There might be two reasons:
1. The touch screen is resistive touch screen, we suggest user using touch pen to click the center cross not finger;
2. It needs about one second touching for calibration, if touching time is too short, the operation will be invalid.

EmbestDevkit8500 2.JPG

Linux problem

How to debug audio applications?

Answer: We are using ALSA audio library, please go to its offical website to download relative material. You would better confirm the ALSA version you used on your target board before downloading. Please get into file system and input: cat /proc/asound/version
After you confirmed the ALSA version, please download alsa-utils-xxx from:
There are source codes of aplay, arecord and more others for your reference.

WinCE problem

Why need touch screen calibration every time when getting into WinCE system?

Answer: Because Embest provides 4.3-inch and 7-inch LCDs for the board, different LCDs use different touch screen parameters, so it needs calibration every time.
However, we can solve the problem as below:
1. Open the Hyper-terminal and boot the WinCE system, do touch screen calibration once and check the Hyper-terminal information, you will see similar sentence like "CalibrationData"="2016,1888 1056,864 992,2912 3040,2976 3072,896", these are parameters of touch screen.
2. Please add the touch screen parameters to BSP path: bsp/file/platform.reg

   ;-- Touch Screen driver --------------------------------------------------------
IF IMGNOCALIBRATION //mask this line
"CalibrationData"="2016,1888 1056,864 992,2912 3040,2976 3072,896" //These are parameters of your touch screen, please modify it to 4.3inch or 7inch
"SPIAddr"=dword:0  ; McSPI1 channel 0
"PenGPIO"=dword:1B  ; gpio27// gpio_175
"PenUpDebounceMS"=dword:28  ; PenUp debounce time in MS, 0 to disable debounce process
"InitialSamplesDropped"=dword:2 ; Number of samples to be dropped after pen down detection
; Default is 1
 ;"SampleRate"=dword:64 ; samples per second, default is 100


Why WinCE BSP could not be compiled successfully?

Answer: if you had installed WinCE compiling environment and want to rebuild the system, but after fully decompressed BSP to the platform directory of wince600 and also used the sln file attached with the software, it still failed. Please follow below ways to check:
1. Please read the user manual to check if the compiling tools have been installed completely; if not complete, it will remind some error informaiton for being lack of some head files; We testing BSP carefully before goods delivery, so this part would usually no any problem;
2. Please check if the folders copied to C:\WINCE600 are right, such as:
Right: C:\WINCE600\OSDesigns\DevKit8500
Wrong: C:\WINCE600\OSDesigns\DevKit8500\Devkit8500
Please do not repeat folders.
3. Please check if you had selected "Build Solution" in "[Build-> Build Solution]" of vs2005 window for compiling accroding to the user manual;
4. Please check if you had added some of your own codes to make the compiling unsuccessfully;
5. After above checking, if you still could not find the problem, please contact Embest support team:, our engineer will give you some help.

DVSDK problem

Why I can only see one partition after TF card partitioning?

Answer: when using DVSDK, you need to prepare a TF card with partition. But we could only see one partition, there might be several reasons:
1. You have seen the only one partition under Windows system, the TF card first partition is FAT, the second partition is EXT3 and EXT3 can only be recognized under Linux, so you can only see FAT partition in Windows;
2. If you can only see one partition under Linux system, please follow below ways:
a) Confirm if you had used ROOT right for partition in your operation;
b) Please operate once again;
c) Change another TF card (please use TF card with good quality as partitioning requires high-quality TF card).

No response when booting u-boot

Answer: when starting u-boot in DVSDK, the hyper-terminal will appear status below:

Texas Instruments X-Loader 1.47 (Feb 17 2011 - 17:33:15)
Devkit8500 xM Rev A
Starting X-loader on MMC
Reading boot sector

1153660 Bytes Read from MMC
Starting OS Bootloader from MMC...
Starting OS Bootloader...

U-Boot 2010.06-rc1-svn ( 5鏈?06 2011 - 10:05:25)

OMAP34xx/35xx-GP ES2.1, CPU-OPP2 L3-165MHz
OMAP3 Devkit8500 board + LPDDR/NAND
I2C: ready
DRAM: 512 MiB
NAND: 512 MiB
In: serial
Out: serial
Err: serial
Devkit8500 xM Rev A
Die ID #2cf600229e3800000163810d19031024
Net: dm9000
Hit any key to stop autoboot: 0 (此处在超级终端串口下按下任意按键)
OMAP3 devkit8500 # setenv bootargs console=ttyS2,115200n8 root=/dev/mmcblk0p2 rootfstype=ext3 rw rootwait mpurate=1000 mem=99M@0x80000000 mem=128M@0x88000000 omapdss.def_disp=lcd omap_vout.vid1_static_vrfb_alloc=y omapfb.vram=0:3M
OMAP3 devkit8500 # setenv bootcmd 'mmc init;fatload mmc 0 80300000 uImage;bootm 80300000'
OMAP3 devkit8500 # saveenv
OMAP3 devkit8500 # boot
OMAP3 devkit8500 #

For normal u-boot, if user inputs "boot" in u-boot, it will excute:
setenv bootcmd 'mmc init;fatload mmc 0 80300000 uImage;bootm 80300000'
If commands have some syntax errors, it might stop the following excution, the problem might be:
1. When inputing some commands manually, you have ignored some space input;
2. You had input more spaces in commands line before inputing other commands;
We suggest copying and pasting the commands directly from pdf files.

   setenv bootargs console=ttyS2,115200n8 root=/dev/mmcblk0p2 rootfstype=ext3 rw rootwait mpurate=1000 mem=99M@0x80000000 mem=128M@0x88000000 omapdss.def_disp=lcd omap_vout.vid1_static_vrfb_alloc=y omapfb.vram=0:3M

setenv bootcmd 'mmc init;fatload mmc 0 80300000 uImage;bootm 80300000'