Vermes
Advanced Member level 4
All new computers have only USB ports, with no COM, LPT nor PS/2. Using FT232RL, you can easily make an adapter USB to RS232, RS422, RS485 as well as implement several unusual operations.
Presented converter has the following features:
- fully automatically converts USB to RS232, without any modifications to the receiving device. Just install the driver on your computer, and the converter will be seen by the system as a COM port
- compatibility with RS232 at TTL voltage levels, so it can be plugged directly to the microcontroller without using voltage converters MAX232 or other. There is a possibility of equipping the converter with MAX232 or another converter to ensure compatibility with the general standard
- baud rate: 3Mbaud
- two output ports: the simplified and full one
- diodes indicating transmit and receive
- miniature size
- a possibility to change the configuration of the adapter using the program supplied by the manufacturer
The simplified port has only the following lines: TxD, RxD and GND, which are the minimum at transmission RS232. Additionally, the port is equipped with Vcc to allow powering the receiver directly from the USB bus. Placing the port pins on the underside of the PCB allows convenient connection the converter directly to the contact plate.
The full port provides all transmission lines RS232 and Vcc. This port was designed specifically for attaching the MAX232. The voltage converter should be connected on a separate board through headers (which are visible only on the 3D model).
In the attachments (original thread) there is a sample program written in Bascom for the test board AVT-3500. The program receives a character typed on the keyboard, display it on the LCD 16x2 and sends back to the terminal screen.
Link to original thread (useful attachment) – Konwerter USB - RS232 TTL