Welcome to the FTDI TTL-232R-PCB examples page.

You have probably arrived here after visiting one of our trade shows and received your free sample of the TTL-232R-PCB kit and are wondering what you can do with it.

The kit contains a PCB which consists of our FT232R USB to UART chip and a USB connector for easy connection to a host PC.

Two lengths of heat-shrink to allow for protecting the PCB after you have decided what wires (if any) you want to solder on to the board. 

This web page is intended to offer some ideas as to what you can achieve with this technology.

Project 1 - Security Dongle

With no additional wiring, you can create a security dongle by making use of the ChipID technology of the FT232R chip to create a secure number that can be encrypted for application access.

The ChipID is a number coded into each device.  Every device has a unique number and so you can encrypt this with your own algorithm and store this encrypted number in the device EEPROM.  The PC with the application you want to use will have the decoding algorithm to decrypt the number  in the user area of the EEPROM and compare this with the device ChipID.  If the two numbers match then the device is successfully decoded and you can access your application.

The black heatshrink provided in the kit will allow you to cover the PCB and offer some protection to the components.  Ensure a minimum of 12mm of USB connector is left uncovered when fitting the heatshrink.  A heatgun should be used to shrink the sleeving.

An ActiveX component called SafeGuard-IT is provided to help set this feature up.  Following the link will provide example code also.

Project 2 - USB to TTL UART Cable

The TTL-232R PCB has 6 pads on it which you can attach a cable to in order to create a cable for connecting to other device UARTs such as MCUs, VNC1L or FPGAs.

• VCC is a 5V signal derived from the USB host port.

• GND is signal GND and should be connected to the GND of your external circuitry.

• RXD is received data and would connect to your external device TXD pin.

• TXD is transmitted data and would connect to your external device RXD pin.

• CTS# is an input to control the flow of data out of the TXD pin.  When at logic 0 data can be sent.  When at logic 1 data is blocked. This would normally connect to the external device RTS# pin.

• RTS# is an ouput to control the external data sending data.  When at logic 0 the TTL 232R PCB can accept data.  When at logic 1 the external device should stop transmitting.

• Slide the small clear heatshrink over the cable you want to solder to the PCB

• Slide the wider clear heatshrink over the cable you want to solder to the PCB

• Solder the wire ends to the PCB pads. For this you will need a soldering iron and solder.

• Then slide the smaller heatshrink sleeve up to the edge of the board.

• Shrink this with a heatgun.

• The wider heatshrink sleeve should now be slid up to cover the PCB and part of the USB connector.  Ensure a minimum of 12mm of USB connector is left uncovered.  This will ensure it can still be plugged into a USB host port.  This will protect your PCB from shorts and spills.

• Shrink this with a heatgun to complete the design build.

Drivers

The FT232R chip used on the PCB requires drivers to communicate to the PC.  This technology has also been developed in-house by FTDI engineers.

The bus layer of the driver is referred to as the D2XX driver and allows you to connect to the device directly.  This is the driver you would use for the security Dongle project.

There is also an upper filter layer known as the Virtual COM Port (VCP) layer.  With this your USB device looks like a COM port on the PC.  This is the version most likely to be used for the USB to TTL UART cable project. 

Driver installation is simply a case of plugging the device in and following on-screen prompts.