J-Link连接TQ2440，出现Unable to halt ARM core 错误？还请高手指教。

TQ2440单板前些天都是好好的，昨天晚上上电后，准备下载bootrom，发现用j-link连接不上，出现如附件那样的信息。电源适配器那里出现吱吱响，电源适配器今天早上拿到公司用万用表量了下后电压5.5V，应该是没有问题。还请高手知道下。

是否是晶振出了问题？我在jlink-arm上，用命令“h”，也还是不能够halt。nor flash 和nand flash多试过了。另外，是否有可能是前些天天气太潮湿了，引起的。我差不多有1个星期没有动那个板子了。

问题找到了！
1，电源坏了；
2，在j-link下使用rx 0命令；
解决方法是从一外国网站论坛上看到得，以下是外国论坛的原文；
Obviously J-Link can "talk" to your chip.
The problem is that it can not halt the chip for some reason.
Most likely cause is that the target CPU has no clock or that
it is performing a memory access which halts the CPU indefinetly.

Can you
a) Check if the CPU has a clock
b) Check if there is a "WAit" Signal which may be active

If this does not help, try "rx 0" from J-Link Commander as follows:

SEGGER J-Link Commander V3.78a ('?' for help)
Compiled Dec 4 2007 22:18:44
DLL version V3.78a, compiled Dec 4 2007 22:18:35
Firmware: J-Link compiled Dec 03 2007 17:15:31 ARM Rev.5
Hardware: V5.30
S/N : 1
Feature(s) : RDI, FlashBP, FlashDL, JFlash, GDB
VTarget = 3.306V
Info: TotalIRLen = 4, IRPrint = 0x01
JTAG speed: 30 kHz
Found 1 JTAG device, Total IRLen = 4:
Id of device #0: 0x3F0F0F0F
Found ARM with core Id 0x3F0F0F0F (ARM7)
J-Link>speed 2000
JTAG speed: 2000 kHz
J-Link>rx 0
Reset delay: 0 ms
Reset type NORMAL: Using RESET pin, halting CPU after Reset
Info: TotalIRLen = 4, IRPrint = 0x01
Info: Resetting target using RESET pin
J-Link>