SERIAL INTERFACE FOR PICS AND VB6

摘要

Many PICproject developers would like to be able to interface their designs with a PC's serial port, but encounter several difficulties. The principal one for those readers using Visual Basic on their PC is that not all versions of VB allow access to the MSCOMM Active-X serial communications control function. Whilst there are "work-arounds" to this problem, they have varying degrees of success. The other problem is that serial port voltages can vary considerably from PC to PC, and these voltages need to be converted to standard TTL voltage levels to enable connection to a PIC. The project described here provides a two-fold solution to this problem. Firstly, a small circuit board is described that allows safe interfacing between a PC and a PIC, or other digital design.