FTDI differences between VCP and D2XX

Question

I have a FTDI FT232R device and am currently trying to figure out whether to use VCP or D2XX. I've read a little about the pros and cons of both, but am still unable to determine which one to use for this project. Since I am going to use Linux for this project, is it even worth the extra effort to use D2XX? Any kind of help or information would be appreciated.

Greetings, Sparkas

Answer 1

Here what I understood from some reading and experience. This list is not exhaustive and I hope that I will be able to improve it with the community answers.

VCP

Pros:

• Built-in inside the Linux kernel

Cons:

• Slower than D2XX? I've being using an FTDI device and its documentation said that there where not using the VCP method because the driver was too slow.

D2XX:

Pros:

• More features: For instance one could use the FT_ListDevices() function to get the list of FTDI enabled devices. This function is not available using VCP.

Cons:

• You have to embed the FTDI library inside the project

VCP: Is the virtual com port which appear as the legacy comm port port like /dev/ttyUSB0. D2XX interface is the proprietary interface for the FTDI devices. D2XX gives much more access to the hardware which are not available by the VCP. Like working in different mode . Asynchronous , synchronous mode or bit bang mode or writing to the eeprom chip.

References:

• http://www.dlpdesign.com/tnt/VCP%20Vs%20D2XX.pdf
• http://www.avrfreaks.net/forum/ftdi-high-baudrate