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Subject: Re: serial interface uses

Re: serial interface uses

From: Chris Muth <>
Date: Thu, 25 Sep 2003 22:44:25 -0500

Hmm, the JBR has a serial port (hardware mod necessary for I/O, and not just input to JBR).
PDAs vary widely in hardware configuration. The question is dependent on the PDA in question.
Various PalmOS based devices should work well. The ones the sync serially and those that can
are excellent candidates. My m505, for example, will work nicely as it has a relatively full featured serial port.

One will probably need a level shifter to convert the RS-232 levels from the Palm to the TTL levels that the
JBR wants.

Virtually all PDAs that use USB, are USB slave devices. It will be a major technical challenge to construct a
USB master deice that will control the PDA and then provide an interface to talk to the JBR via some sort of
RS-232 like interface. Getting the PDA/Palm to use the USB port for anything but syncing might also be more
difficult than just opening the serial port and sending bytes out.

Just modding the JBR to have a serial I/O port, building a level shifter, and then building a cable with the shifter to
connect the PDA/Palm to the JBR would much less trouble.

There are plans for a level shifter here <>.


On 9/25/03 at 8:50 PM Glenn Ervin at home wrote:

>What kind of cable would one get to connect the JBR to a PDA?
>Would we get a USB to serial null modem cable?
>----- Original Message -----
>From: "Steve Russell" <>
>To: <>
>Sent: Wednesday, September 24, 2003 4:40 PM
>Subject: Re: serial interface uses
>"Will" <> wrote in message
>> I'd love a good, inexpensive remote, with or without an LCD screen. You
>> can order one from archos for $20 and then pay another $10 for shipping
>> handling. I was considering just building one but don't have a PIC
>> and can't find a four pin interface plug. I would think a standard
>> interface chip would work for the controller but without the plug I can't
>> do anything anyway.
>My PIC-based remote design is available at
Received on 2003-09-26

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