USB to serial PC peripheral device

USB based device.
This project is just a template for many other projects to come, but forms an important building block for any devices that you wish to connect to your PC. It uses the FTDI chip FT232RL to convert signals from your PCs USB port to serial signals (TTL level +5v not RS232 levels) that can be used directly by a PIC microcontroller.

The FT232RL is a USB-to-serial chip from FTDI
In this example, we use the VCP driver to create a virtual COM port on the PC.
Sending data to our device via USB is simplified - data can be sent to and from the virtual com port just like an "old-fashioned" serial port. By default the virtual COM port is created at 9600 baud, 8 bit, no parity. The code in both the device (microchip) and application (VB app) use these settings so that users are not put off by the need to poke about in the Device Manager.
The actual COM port number that is assigned to your device depends on your PC and how many other COM ports are already in use or available to the computer. On most modern machines, COM1 and COM2 are assigned and the next available port is called COM3 (although if you have already used another device that uses the FT232 chip, such as a PIC programmer, COM4 or even COM5 may be assigned to your device).

Once you have installed the VCP (virtual com port) driver on your machine, your device will be detected by Windows as soon as it is plugged in. It will automatically create a new COM port (which is removed when you unplug the device). You should always make sure that the user can set the COM port to talk to your device in the application software (in this case, the VB application).

The FT232RL chip most often comes in SSOP package which is a very small chip.
You can also get them ready-mounted onto a "breakout board" which converts them into a DIP-style package so that they can be used with a regular breadboard prototyping system. For production boards, you can use drag soldering to solder them to your own PCBs.

Is depreciated the right word?
It turns out that it was a useful proof-of-concept project, but ultimately if you can afford to shell out six quid for an FTDI chip on a breakout board, there's no reason why you couldn't sink £3.99 into an 18F series PIC microchip with built-in USB and cut out the middleman!
See the Nerd Club projects for examples of how to use USB in your PIC-based projects and forget all about this chip - unless you're working with existing legacy hardware, there's no real need to use the FTDI USB-to-serial chip in your own projects any more!