TI中文支持网我们自制了一块DM8168的板子，现在正处于调试阶段。最近一直卡在ddr3初始化这块，现在内核能够连上，但是用Ti816x_ddr.gel文件配置板子时，会报错“CortexA8: Trouble Writing Memory Block at 0x4c000010 on Page 0 of Length 0x4: (Error -2130 @ 0x4C000010) Unable to access device memory. ”有的工程师说我们板子的ddr走线有问题，不知道怎么能确定问题的真正所在，请赐教，谢谢大家！
具体报错log信息如下：
CortexA8: Output: Device type is GPCortexA8: Output: DM816x Main PLL Init is in Progress, Please wait …..CortexA8: Output: DM816x Main PLL Init is Done …..CortexA8: Output: DM816x DDR PLL Init is in Progress for 796.5 MHz DDR Clock, Please wait …..CortexA8: Output: DM816x DDR PLL Init is Done …..CortexA8: Output: DM816x DDR2/3 PRCM Init is in progress …..CortexA8: Output: DM816x DDR2/3 PRCM Init is Done …..CortexA8: Trouble Writing Memory Block at 0x4c000010 on Page 0 of Length 0x4: (Error -2130 @ 0x4C000010) Unable to access device memory. Verify that the memory address is in valid memory. If error persists, confirm configuration, power-cycle board, and/or try more reliable JTAG settings (e.g. lower TCLK). (Emulation package 5.0.710.0)DDR3_796MHZ_doall() cannot be evaluated.
target access failed
at *((unsigned int *) (0x4C000000+0x10))=(unsigned int) (0x10000000|SDREF) [Ti816x_ddr_LP_TI.gel:225]
at EMIF4P_Init(0x1557B9AD, 0x405F7FEB, 0x001F857F, (0x10001844&0xfffffff), 0x62A73832, 0x00000110) [Ti816x_ddr_LP_TI.gel:1766]
at DM816xDDRPLL_796() [Ti816x_ddr_LP_TI.gel:1357]
at DDR3_796MHZ_doall()
CortexA8: Trouble Reading Memory Block at 0x20094 on Page 0 of Length 0x25: (Error -1205 @ 0x20094) Device memory bus has an error and may be hung. Verify that the memory address is in valid memory. If error persists, confirm configuration, power-cycle board, and/or try more reliable JTAG settings (e.g. lower TCLK). (Emulation package 5.0.710.0)CortexA8: Trouble Reading Memory Block at 0x20094 on Page 0 of Length 0xd: (Error -1203 @ 0x3D5B) Unable to access the DAP. Reset the device, and retry the operation. If error persists, confirm configuration, power-cycle the board, and/or try more reliable JTAG settings (e.g. lower TCLK). (Emulation package 5.0.710.0)
CS_DAP_DebugSS: Failed to remove the debug state from the target before disconnecting. There may still be breakpoint op-codes embedded in program memory. It is recommended that you reset the emulator before you connect and reload your program before you continue debugging
CortexA8: Power Failure on Target CPUCortexA8: Failed to remove the debug state from the target before disconnecting. There may still be breakpoint op-codes embedded in program memory. It is recommended that you reset the emulator before you connect and reload your program before you continue debugging
Eason Wang：
如果是走线有问题导致的DDR3信号质量问题， 一般可以用降低DDR3的频率的办法来验证通过的。
你直接在gel文件里面把DDR3的频率降低看看吧。
peng ling：
回复 Eason Wang:
Eason Wang：
你好！谢谢你的解答，通过降频可以通过，打印信息如下：
但我按照wiki里ddr3_init文档，运行the Slave Ratio Search Program 后，按F8没有打印信息，请问问题可能出现在什么地方？
您们有什么测试程序可以让我确认板子DDR3 部分是否有问题，因为我们自制的这块板子接串口，没打印信息。
期待您的答复，谢谢
Eason Wang：
回复 peng ling:
http://support.spectrumdigital.com/boards/evm816x/revd/
这里有DDR3的测试文件（基于CCS的）
