Andy:
The problem is sloved.

In ST 3234A, it contains two flashes. Main Flash and Secondary Flash, ST uses Secondary Flash as default Boot Rom, but its size is 32K only(0-7FFF), I want BOOT rom has 64K space , I used Main Flash instead. The ST3234A Main Flash has 8 sectors. I only defined two sectors FS0(0-7fff) and FS1(8000-FFFF).ST provides software that we can download our HEX file through JTAG. Yesterday why I issued LJMP 8000H command didn't work is I forgot to tell FS1 to pick up the same HEX file as FS0. In their software, we must let FS0 and FS1 pick the same HEX file, yesterday I left FS1 part pick hex file edit box blank, even if i wrote the something to address above 8000h and downloaded the hex file to ST CPU, FS1 sector got nothing and was in blank status. so the code didn't run.

Maybe my experice will be helpful for other guys want to use ST uPSD CPU.

Thanks.

Frank