I'm using keil c51 7.05 Problem is that uVision can connect to mon51 only in win98 environment. In win2000, or winxp it fails to connect. Does any body have solution? TIA!
You must have specialy driver for port "userport.sys" for operating system WIN2000 or later.
Sorry, but I do not have this DLL on my Windows 2000 computer and the serial communication just works fine. So it must have to do with specific hardware.
where is userport.sys ?
"where is userport.sys ?" Given that Keil support themselves don't have it, this appears to be a red herring. However, you still haven't answered the questions about your serial port hardware.