lpc2132 doesn't respond me :(

Hello;

I am an almost a newbie on ARM/ I was trying to figure out how to configure a startup.s file. I worked on PLL settings a little and after that it started not to respond me. please note that I use different board and flash program (H-JTAG).

I have found that If I load a wrong pll settings , it won't respond me any longer until I load the correct settings manually.

Then, I tried to load correct setting via ISP. But whatever I have done , The micro doesn't enter the isp mode.

Thanks, Any help will be welcome

Adem