Picture of Assembling a RS232 to TTL Serial Adapter
Step by step assembly of the RS232 to TTL Serial Adapter kit from moderndevice.com.

This is a great option for connecting the Arduino or Arduino clone to a plain old serial port. It mates directly with the BBB or RBBB or the pins can be remapped to fit other devices.
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Step 1: Resistors

Picture of Resistors
Place the resistors in the R1 (10K, Brown Black Orange), R2 (22K, Red Red Orange), R3(180 Brown Grey Brown), R4(10K Brown Black Orange), R5 (10K Brown Black Orange) spots. Orientation doesn't matter.

Solder them in and clip the leads.

Step 2: The diode

Picture of The diode
Place the diode in the D1 spot. There is a black line on the board to show the orientation of the diode. Place the black bar on the diode towards to line on the board.

Step 3: Capacitors

Picture of Capacitors
The capacitors are placed in the C1 and C2 spots. Orientation does not matter.

Step 4: The DB9 Connection

Picture of The DB9 Connection
Slide the board between the lugs of the DB9 connector. Note there are 4 pads on one side of the board and 5 on the other. These match the lugs on the connectors. Solder it up.

Step 5: The Chip

Picture of The Chip
Add in the chip. You will need to squeeze the legs in a bit to get it to fit. Pay attention to the orientation. The notch on the chip should match the notch in the picture on the board.

Step 6: The Headers

At this point you may add whatever header style you wish, male or female, in whatever configuration you wish, up or down, straight or 90 degree bend.

The kit comes with straight male headers.

In this configuration you may plug this directly into a RBBB or BBB.

Step 7: Header Options

Picture of Header Options
If you wish to use a device with different pinouts than the BBB or the RBBB you may cut the traces between the first and second line of header holes. Then simply pace jumpers to match the needed pin configuration.

Step 8: Connect it!

Picture of Connect it!
Shown here is the adapter connected to a RBBB.

Good luck and happy coding!
diy_bloke3 years ago
How would this go straight into the RBBB as that one has 6 pins and the serial adapter only 5:

RBBB adapter
GND Reset
shad0w885 years ago
Does this need to be bought from moderndevice or can we buy the components separately and make it.

I'm concerned about the chip if it is programmed then i'll have to get it from moderndevice otherwise i can get everything seperately.

youevolve (author)  shad0w885 years ago
No programming needed. This is a Hex Inverter 74HC04
Mouser part # 511-M74HC04

The schematics can be found in the instruction sheet for the kit.
which can be found here:
modeve5 years ago
Just want to point out that the newer version of this board connects to the six pin headers on the right side of the RBBB board
russ_hensel6 years ago
Nice job. I have add a link to your instructable here: http://www.opencircuits.com/RS232#More_on_Level_Shifters
where there is more info. on this topic.