DDR时钟

挂载CCS看一下？

DDR的其他信号呢？你应该用了2组DDR控制器吧，另外一组也是这样吗

做了几块板子，都是一样现象？

Louis:

      您好！谢谢您给我的建议！我换了一个1.5G 的探头，测了一下差分时钟是800M,幅度是200mv，波形规整，如下，麻烦您看一下这样的差分时钟能达到标准吗？

我也按照您的建议连了一下CCS，test connection 的结果如下：

会提示“target power loss”错误。launch the dm8168 以后会出现下面的情况：

这样的情况，能说明ccs能够连接吗？期待您的回复，谢谢！ 

  从波形截图上看，看不出CLK信号有什么问题。 另外DDR时钟查分信号上的终端匹配电阻是多大的？是否满足DATASHEET的要求？尝试把这那两个匹配电阻去掉看是否有改善。 另外，你的仿真器连接其他的板子是OK的么？请先确认仿真器是否工作正常。具体步骤可以看一下：http://processors.wiki.ti.com/index.php/DM816x_AM389x_PSP_Flashing_Tools_Guide

Starting CCS
• System Requirements – CCS version 5.1.0.05000 installed on Windows XP
• Make sure the Boot Mode / Configuration Select Switch is set for the respective boot mode
• Connect the XDS560 emulator to the EVM
• Start CCSv5 by navigating to 'Start' menu in Windows XP
• Use target configuration file  tools/DM816x.ccxml. If there is a need to create a new configuration, then follow
steps below:
• Select "View -> Target Configurations"
• In the "Target Configurations" tab select "New Target Configuration File" button (in the top left corner)
• Name the file (eg. ti816x_usb.ccxml)
• Connection = Spectrum Digital TI XDS560V2 STM USB Emulator
• Board or Device = TI816x | TI814x |TI813x * select the connected device from the list
• Save configuration
• From next run, the project and target configuration will be readily available and can be skipped
• Select "Debug Perspective" in CCS if not there already: "Window -> Open Perspective -> Debug"
• Select "View" -> "Target Configurations"
• Expand "User Defined" configuration tree, Right click on the newly created target configuration and select
"Launch Selected Configuration"
TI81XX PSP Flashing Tools Guide 2
• This should launch debug session
• In Debug view, (scroll till the end) Select "Spectrum Digital TI XDS560V2 STM USB Emulator_0/Cortex
A8" connection.
• Right click on the Cortex A8 core listed and click on "Connect Target"
• A "Dissassembly" view with PC halted should pop up in one of the tabs. If not, do a 'System Reset' from Target
menu and then Halt (for GP device)

Regards,

Louis

Louis:

       您好！差分线上的匹配电阻已经去掉，对时钟信号的幅度有一定改善（现在是0.25V）。按照您的建议，我用仿真器（我用的是Blackhawk USB560-M Emulator）连了一下6670开发板，结果OK，说明仿真器没问题。连上仿真器，不管我对板子加电与否，test connection 的结果都是"The controller has dected a target power loss" ,如图：

进入Debug界面，右键点击“ the Cortex A8 core”，然后点击"Connect Target"，显示结果如下请问可能是什么原因导致连不上CCS，该怎么解决，请赐教，谢谢！