Alchitry Cu Serial Interface

in the schematic I can see, that two pins of the ICE40 are connected as RxD and TxD to the FTDI chip. Is this a serial interface to communicate the FPGA?
If yes: how do I connect to on PC side? The FTDI did not appear as /dev/tty* device on my Linux machine.


I’m not sure how to do it, however my intuition is that you need to make the serial port actually do something. Looking at the code in au_top.luc (it should be similar enough to cu_top.luc) it looks like by default it simply echos the incoming serial data making the computer that it’s connected to think that its not actually connected to anything worth sending data to.

I did some research: The FTDI can be controlled via the libftdi library. For quick and dirty stuff there is also a python package called pylibftdi that is based on the library.

The FTDI has two interfaces A to flash the Cu and B to communicate with the FPGA.

So the Device has to be initalized as follows (in python):

[code]from pylibftdi import Device

device = Device(interface_select=2)

Then I was able to send/receive to/from the FPGA with the read() and write() methods.
The baudrate can be changed with

device.baudrate = 300

to 300 Baud in this example.

The Python package is documented at
And the library at