Try to configure the Arch Mix to Arduino according to described procedure.
Without the J link it state to connect the RX pin to 3.3v pin. There are several RX pins. Which io pin should I connect?
I realize this reply is months late but I just got started with my Arch Mix board last week.
I used a Segger J-Link Mini (EDU) to flash the Arduino bootloader. The directions on the wiki were almost complete for using the J-Link Mini, it was missing the instructions to attach the voltage reference signal.
Here is how mine was wired up.
Arch Mix ==> J-Link Mini
SWC Pin J4_19 ==> Pin 4 CLK
SWD Pin J4_20 ==> Pin 2 DIO
GND Pin J4_21 ==> Pin 3 GND
3v3 Pin J4_22 ==> Pin 1 VREF