Adding a Serial Console


We have 'standardised' on placing the console on the J4 uart.

J4/J5 Pinouts:

     Pin     
Function
Notes
1
GND

2
Input

3
Output


(@buserror) You can easily add a serial console for debugging by routing the J4 pins to the side of the board and add a header there. You can also take 5V from the JTAG connector and have a header compatible with most TTL serial adapters (FTDI or others).

(Click for a bigger image)


(@Biff) As an alternative, if you're using a USB-serial adapter and don't need the power pin you can solder a header onto the back of the PCB, and make a hole in the back of the case for it:
(Click for a bigger image)

Advantages:  No glue or kynar wire required, just a PCB header, might be quicker.
Disadvantages:  Can't lay the screen flat, and need to ensure the solder-side leads are clipped back so they don't touch the LCD panel.  Also, J4 comes out quite close to the right button!

I did it this way partly because I wanted the JTAG brought out as well.  Regarding the JTAG, you have to be careful doing this, because it then becomes the wrong way round, but since I had to make up my own cable anyway it didn't matter.

If you want to see something when connecting to J4, the original Parrot firmware, u-boot and the kernel are all configured to use the port at 115200 baud.

For what you can expect to see on J4, see the Boot logs.
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