sir i am doing a project of displaying pc time in seven segment displays.
i use the parallel port to pass the bcd coded data of hour and minutes and display them by using 4 7segment displays. Here i used a bcd to seven segment decoder to convert the bcd code. now when i give the input manually to the board the led glows and works correctly, but when i give data from pc its doesnt works
i cant identify the problem pls do help
Are you sure the PC is outputting the signals? You didn't say what software you are using, so I'm guessing that you wrote a program that runs under Windows XP or 2k. Those operating systems prevent user programs from accessing I/O ports, unless you install a kernel mode device driver such as PortTalk. There's a link to it here: **broken link removed**