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PicoStation2 RS232 Connection

This document will show you how to use the RS232 serial connector to access the device's console. This allows you to directly access Redboot, debug any boot issues with your kernel, and access the terminal of your firmware even if you don't have telnet or SSH access.

A small note to remember is that with some TTL level converters, having it plugged into the wireless unit before powering the unit on can cause the unit to not boot. For this reason, always power on the unit, then attach the cable immediately after.

What you will need

Tools and items you need

• PicoStation2 (obviously)
• 3.3v TTL RS232 level converter (we'll use one that is integrated into an USB cable - TTL-232R-3V3)
• Small phillips screwdriver
• *Very* small slot screwdriver

Open your PicoStation2

Remove the antenna and cover

Peel up the label on the back side of the unit and remove both screws

Gently pull the board out of the unit

Prepare the TTL Level converter

Removing wires from a header connector 3.3v TTL Header on the PicoStation2 Correctly wired TTL-232R3V3 connector Your level converter needs to be pinned to match the pinout of the unit. Lets first remove the cables pins from the connector. using your small flathead, lift the little plastic flap, and pull out the wire, for each wire. Set the connector aside. Now, you'll see the board has a 4 pin header on it, with labels for each pin. The ones you care about are SIN,SOUT,and GND. SIN connects to your cable's TX SOUT connects to your cable's RX GND connects to your cable's GND In our case, using a TTL-232R3V3, we'll put the wires back into the connector so it looks like the bottom picture on the right. Now, plug the cable into your computer - but don't connect it to the wireless unit yet!

Conclusion

Correctly connected TTL header

PicoStation2 Booting

You're now ready to access the console using a terminal program of your choice.

Follow the directions for your terminal program at Connecting to the AirOS serial console