请高手来帮忙看看，程序执行不了啊

我用的芯片是5402<br />程序可以下载和运行,但是每次只要涉及到端口的指令就执行不了,比如用PORTW,PORTR给I/O空间送数据或读取数据时,会有出错信息:<br />can't&nbsp;single&nbsp;step&nbsp;target&nbsp;program:<br />Error&nbsp;0x80000020/-1058<br />Fatal&nbsp;Error&nbsp;during:Execution,<br />Device&nbsp;driver:&nbsp;Emulator&nbsp;Controller&nbsp;not&nbsp;responding<br />It&nbsp;is&nbsp;recommended&nbsp;to&nbsp;RESET&nbsp;EMULATOR&nbsp;.&nbsp;This&nbsp;will&nbsp;disconnect&nbsp;each&nbsp;target&nbsp;from&nbsp;the&nbsp;emulator.&nbsp;...<br /><br />Trouble&nbsp;Reading&nbsp;Target&nbsp;CPU&nbsp;memory:&nbsp;Cannot&nbsp;access&nbsp;memory&nbsp;<br />address&nbsp;0xFA.<br />接下来连程序下载也不行了.提示下载失败:<br />Trouble&nbsp;Reading&nbsp;Target&nbsp;CPU&nbsp;memory:&nbsp;Error&nbsp;0x00000002/-2140&nbsp;Error&nbsp;during:&nbsp;Memory,&nbsp;&nbsp;Cannot&nbsp;access&nbsp;memory&nbsp;address&nbsp;at&nbsp;0x00002493<br />Trouble&nbsp;Reading&nbsp;Target&nbsp;CPU&nbsp;memory:&nbsp;Error&nbsp;0x00000002/-2140&nbsp;Error&nbsp;during:&nbsp;Memory,&nbsp;&nbsp;Cannot&nbsp;access&nbsp;memory&nbsp;address&nbsp;at&nbsp;0x0000249D<br />Trouble&nbsp;Reading&nbsp;Target&nbsp;CPU&nbsp;memory:&nbsp;Error&nbsp;0x00000002/-2140&nbsp;Error&nbsp;during:&nbsp;Memory,&nbsp;&nbsp;Cannot&nbsp;access&nbsp;memory&nbsp;address&nbsp;at&nbsp;0x000024A7<br />Trouble&nbsp;Reading&nbsp;Target&nbsp;CPU&nbsp;memory:&nbsp;Error&nbsp;0x00000002/-2140&nbsp;Error&nbsp;during:&nbsp;Memory,&nbsp;&nbsp;Cannot&nbsp;access&nbsp;memory&nbsp;address&nbsp;at&nbsp;0x000024B1<br />Trouble&nbsp;Reading&nbsp;Target&nbsp;CPU&nbsp;memory:&nbsp;Error&nbsp;0x00000002/-2140&nbsp;Error&nbsp;during:&nbsp;Memory,&nbsp;&nbsp;Cannot&nbsp;access&nbsp;memory&nbsp;address&nbsp;at&nbsp;0x000024BB<br />Trouble&nbsp;Reading&nbsp;Target&nbsp;CPU&nbsp;memory:&nbsp;Error&nbsp;0x00000002/-2140&nbsp;Error&nbsp;during:&nbsp;Memory,&nbsp;&nbsp;Cannot&nbsp;access&nbsp;memory&nbsp;address&nbsp;at&nbsp;0x000024C5<br />Trouble&nbsp;Reading&nbsp;Target&nbsp;CPU&nbsp;memory:&nbsp;Error&nbsp;0x00000002/-2140&nbsp;Error&nbsp;during:&nbsp;Memory,&nbsp;&nbsp;Cannot&nbsp;access&nbsp;memory&nbsp;address&nbsp;at&nbsp;0x0000237B<br />

斑竹来帮帮忙啊

兄弟门,都没碰到过这种情况吗?