SerialAdaptor-3.3v5v

Goal

Group ordering of USB Serial Adaptors (which does 5v out of the box, and 3.3v with a hack) for serial console on routers, such as OpenWRT.

Picture

Price

15EUR (+1.5EUR shipping)

Problems

The Vccio is connected to 5v (usb 5v), so the output voltage on TX is 5v: this means you can only use this board to connect to 5v tolerant electronics (like the Fonera). To add 3.3v support, we did a small 3.3v hack.

3.3v hack

We did a small hack to add 3.3v support, which consists of two simple steps. Note that you have to keep the jumper connected. When the jumper is not connected, the voltage is floating, and there is a need to make a second hack to get use the 5v :-).

Step 1: drill a head

Drill the head of the whole connected to pin4 on the back of the board:

Step 2: solder a wire

Solder a wire between the 3.3v pin and the XXX pin:

Online Shop

Tektonica

Deadline

Tuesday 17 Nov 2009 @ TechTue32

People ordering

1. Pierre
2. zoobab (delivered+paid+hack3.3v)
3. ptr_ (delivered+paid+hack3.3v)
4. SkyNETbbs (delivered+paid+hack3.3v)
5. Kyros Hariri (delivered+paid+hack3.3v)
6. Yanu (delivered+paid+hack3.3v)
7. nicodache (notdelivered+paid+hack3.3v)
8. pweemeeuw (delivered+paid+hack3.3v)
9. pastec2 (delivered+paid+hack3.3v)
10. dee
11. Askarel (delivered+paid+hack3.3v)
12. Xflame (delivered+notpaid+hack3.3v)

Status

• Fri 20 Noc 2009: 12 adaptors ordered, transfer sent
• Wed 25 Nov 2009: the adaptors has arrived, contact me at zoobab at gmail.com or +32-484-566109 to fetch them
• Fri 27 Nov 2009: adaptor tested with a fonera serial connexion
• Dec 2009: Pastec made the 3.3v hack

Linux support

When you plug it in, here are the kernel messages:

[   74.316066] usb 6-1: new full speed USB device using uhci_hcd and address 4
[   74.509490] usb 6-1: configuration #1 chosen from 1 choice
[   74.513157] ftdi_sio 6-1:1.0: FTDI USB Serial Device converter detected
[   74.515847] usb 6-1: Detected FT232RL
[   74.515909] usb 6-1: FTDI USB Serial Device converter now attached to ttyUSB0

Pinout

Links

• http://arduino.cc/en/Main/MiniUSB
• http://www.lefinnois.net/wp/index.php/2009/04/15/ttyusb0-ttyusb2-non-ttyusb1-graaaahh-udev/
• http://www.lefinnois.net/wp/index.php/2008/10/23/adaptateur-usbserie-ttl/
• http://www.flickr.com/photos/roy_vanegas/sets/72157621000124886/
• http://i5.be/Vw
• http://www.sgbotic.com/index.php?target=products&product_id=48