Driving Relay from Parallel Port (LPT)

Driving relay from parallel port (LPT) using Delphi or Lazarus component

Simple Serial Downloader for AT89S51/AT89S52

SDownldr.exe is a software to program a AT89S51/AT89S52 serially through the parallel port. This Software is included in the Microcontroller Project Circuit diagram for this ISP downloader is as follow: The Serial Downloader circuit above using the power supply from the parallel port. However, not all parallel port capable of providing enough current for this […]