Laptop debug

[Mitch Bradley]

As an alternative to wiring up a voltage converter chip, you can instead 
go directly to USB with a USB-to-serial chip such as a PL2303.

The "traditional" arrangement is:

  USB-to-serial dongle   -> DB9 -> serial cable -> DB9 -> 
12V-to-3.3V-voltage-translator

But inside the USB-to-serial dongle there is:

  USB-to-serial-chip -> 3.3V-to-12V-voltage-translator

So the chain:

  3.3V-to-12V-voltage-translator  -> DB9 -> serial cable -> DB9 -> 
12V-to-3.3V-voltage-translator

is essentially a complicated hardware "no-op".

There is little difference in the complexity of wiring up the 
USB-to-serial chip versus wiring up the voltage translator chip.

John Watlington wrote:
> No.  You can use a standard USB/RS-232 serial converter, but
> you will also need a voltage translator (such as a Maxim MAX3233 ---
> you used to be able to get free samples from Maxim) and a male and
> female connector to connect to the board.   I'll dig up the connector
> spec (Digikey carries them) and pinout and post them on the Wiki
> soon.  Remind me if you are in a rush.
>
> The debug adapters cost us around $100 to make, due to the small
> quantity built.  We treasure them dearly, as we sometime need 50 or
> more in a testbed!
>
> wad
>
> On Dec 20, 2007, at 12:16 PM, Gerard J. Cerchio wrote:
>
>   
>> Hi All,
>>
>> Do the XO's ship with the serial/USB debug adapter?
>>
>> If not, how do I get one?
>>
>> -Gerard
>>
>>
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>>     
>
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