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H2
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H2 - Communications
Serial
A LVTTL level serial connection is available on a 10 pin FFC connector on the support board. This can either be used to get a terminal connection, or to interface to external devices (GPS receiver, touchscreen, etc.). A LVTTL to RS232 level converter board with DB9 and 10 pin FFC connectors is also available for terminal connections.


Serial Adapter

The serial terminal is useful for transferring files (using command line tool rz), debugging, and prototyping operations sequences.

Bluetooth
The Gumstix SBC is available with a bluetooth transceiver from Infineon (ROK 104 001/2R1A). Currently this has only been tried using a rubber duck style antenna plugged in outside the H2 case. Relocating the antenna connector or using a smaller antenna could make this a more reasonable scenario.


Bluetooth model with antenna

So far we have only used the bluetooth capability to establish a terminal connection from a PC using a USB bluetooth adapter (Belkin F8T003 on Win2K with USB/Bluetooth software installed). However, images can be transferred using rz over this terminal connection, e.g.:

sh> cd /tmp sh> rz

- use zmodem to send test.ppm.bz2 from host side via terminal - file will end up as /tmp/test.ppm.bz2.

One thing to remember about rz is that it won't overwrite files, so if you wanted to send an updated test.ppm.bz2, you would need to delete the old one first.

There are lots of fun software projects one can imagine doing using this interface. For example, H2 could be updated remotely from some external device like a print server, weather feed, or BT equipped cell phone.

We have experimented with obex file transfer over BT as well, but have not gotten it working quite yet. It sure seems like bluetooth is a bit flakey in general, even using a PC.

USB
The Gumstix board supports a USB connection, and can be configured as a USB device. The most current support board has some pads that a Mini-B connector might be jumpered to.

Design partially original and partially ripped off from other websites
by Holly Gates