Adding a serial port to a QNAP TS-251D

Connector

I am using a QNAP TS-251D NAS. Because I would like to switch from QTS to Alpine Linux I though it would be useful to enable the serial port.

The TS-251D has a built-in serial port that is already enabled and only needs to be connected. For that you need a number of parts:

In addition, I am using a 3D printed bracket to hold the serial port.

Examinig the QTS environment you can see that there is indeed a /dev/ttyS0 device (a serial port) and it is enabled in the Kernel command line with:

console=ttyS0,115200n8

Simmilarly you can find in the /etc/inittab a line:

ttyS0::respawn:/sbin/getty -L ttyS0 115200 vt100

So there is a serial port available and being used for debugging.

To make it visible to the outside, you only need to connect to JST1

Connector

Pins from left to right.

  1. GND
  2. RX
  3. VCC
  4. TX

For the bracket to hold the serial port I printed this 3D Model.

Place the Serial module on the 3D printed bracket.

Bracket

And mount it on the case:

Case with bracket1

Case with bracket2