[c-nsp] USB to Serial Converter recommendation

[Christopher.Marget at usc-bt.com]

> - is compatible Mac OS X,
 
> *- knows how to send breaks (the must have feature),*

On OSX there's a great terminal emulator called ZTerm, written by Dave Alverson.

It supports a nifty feature to send BREAK even when your hardware or drivers don't support it.

BREAK amounts to holding the TX pin high for longer than the duration of a character.  It's not a character.  It's more like a framing error.

High voltage on the TX pin is a binary zero.

To send the unsupported BREAK, ZTerm briefly the baud rate, then sends the ascii NUL character (binary zero).  The string of zero bits at (say) 300 baud looks exactly like BREAK to your 9600 baud router console.

Works great!

As for choosing a USB dongle, I'm partial to anything with a PL2303 chip inside.  These are well supported on lots of platforms, and can usually be had for almost nothing: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=350320547894

/chris