So I'm trying to detect through Visual Basic 6.0 when a voltage change occurs on one of the pins of the serial/parallel port. The whole thing is pretty simple; no data transfer/handshaking/etc ...

Okay, I was thinking last night about a possible mod, and have some questions.My idea was to use an old VU meter or analog voltage meter as a processor usage meter to put on the front bezel of my ...

But the problem is that an RS232 serial port operates with 12V logic levels and the JTAG side of the programmer needs to operate with the logic levels native to the device you’re programming.