Interfacing MCU to FT230 for MCU and PC communication

[tazcast]

I want to connect PIC18F66K22 MCU to PC via USB. To do this, I used FT230 chip to interface the MCU to the PC via USB port.

I want to send and receive data from MCU to a Windows PC (via Hyperterminal).

I have connected the Ft230 as in the following photo.


However, when I connect the MCU to the PC, there is no communication between PC and MCU.
There is no display on hyperterminal.

Does anyone have an application note on how FT230XQ is interfaced with an MCU?

Do I need to set some parameters on the FT230XQ to be able to allow communication between the MCU to a PC?
Do we need to set the baud rate before we can send and receive data?

What pin connections are connected from MCU to FT230XQ?

Thanks!

 

[FvM]

Connecting only RxD and TxD is OK with no handshake selected in Hyperterminal (default). Of course the processor UART must be set to the Baud rate programmed in Hyperterminal.

 

[tazcast]

The baud rate of the MCU is not really set to exact 9600bps (9615bps actually) like the setting on the Virtual com port which is 9600bps. Is this OK?

If I connect an oscilloscope on TXD pin of the MCU, signal is changing so it means data is going out. But when I connect the TXD of the FT230XQ going to RXD of the MCU, there is no change in the signal when I send data from Hyperterminal to MCU.

 

[techgreed]

Is the FT230X detected in PC as COM port?
If the connections to the FT230 are correct, it will be detected. Confirm this first before going to check onto the MCU side.

 

[tazcast]

Yes, FT230X was detected, I can even change the settings on device manager. Drivers were installed correctly as well. The problem is that the FT230X does not translate the data from the PC going to MCU.

 

[FvM]

Are you sure that the used virtual COM port is owned exckusively by the FTDI driver? Has it been chosen automatically during installation or did you edit the port number?

RTS# should change state from H to L when connecting to the virtual COM port.

 

[tazcast]

Yes. It has been chosen automatically. It has chosen COM5.

 

[techgreed]

Have you tried the echo test?
Short the lines Rx&Tx and try sending some data from hyperterminal and see whether its received back. If the data gets received back, we can ensure that FTDI chip is fine.
Then try the same in the controller. Short Rx&Tx lines and send something to the uart port of the controller and see whether its received back. If it doesnt, you will have to check your code again.

 

[laser-speed]

Hi every one ... For ATMEGA644 I use the MOSI, MISO, SDK, Reset lines for programming ... then if I want to establish communication to drop commands to the program I use the RX&TX lines ... I'm using the FTD232RL USB-UART chip ...
So If that applies to the PIC18F66K22 so that could be the reason