Milkymist JTAG-serial daughterboard

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JTAG-serial daughterboard on Milkymist One RC1

[edit] notes (need to be cleaned up)

never hot-plug the daughterboard, both Milkymist One and daughterboard need to be powered off when they are being connected
after pluggin in USB, power LED at bottom left should always be on
Depending on your Linux version, the daughterboard will appear as either one or two /dev/ttyUSB* devices. If two devices appear, the first one corresponds to the JTAG interface, and is not directly usable, the second one implements a serial interface to the MM1 SOC. On newer Linuxes that know the MM1-JTAG's USB-ID, only the second device (the serial console) appears.
Connect to the console via gtkterm -p /dev/ttyUSB1 -s 115200 (use /dev/ttyUSB0 with newer Linuxes), then try

 %
 % help
 % ls
 % ... (see commands with 'help')

run ls, check that tx and rx leds are working
Now you can also to access the JTAG interface via xc3sprog -c ftdi (need to run as root). Check that Desc: is XC6SLX45.
For programming the MM1-JTAG interface itself, use:

 libftdi
 FTDI - FT Prog (also works when daughterboard is not connected to Milkymist One).  Need to change: PID, VID, Description;

- Manufacturer: FTDI (default), Sharism, Milkymist?
- Product description: Milkymist JTAG/serial
- SERIAL: to distinguish between multiple devices connected at the same time
- SerialNumber / Auto Generate Serial
Hardware Specific, Port A, Hardware, from RS232 UART to 245 FIFO (maybe) (others: CPU FIFO, OPTO Isolate)
When USB is connected, but not the M1 board, connecting with gtkterm and, pressing enter will make TX led blink
- left one = tx = send to m1 board
- right one = rx = receive from m1 board
- xc3sprog: error will be "No JTAG Chain found" (otherwise: "Could not find USB dongle")
it took Yanjun Luo 1h/board for manual mounting