Re: USB module for monitoring multiple on/off switches

["Josepi" <JRM@xxxxxxxxxxxx>]

Makes sense and cheap but you did mention serial port.

WTF is a "buss"? (obviously you work in the electrical field)


"J Miller" <reply@here> wrote in message
news:4ae11e73$0$89394$815e3792@xxxxxxxxxxxxxxxxx
> Josepi wrote:
>> RS-485 is a two wire serial port that can support multi-drop peripherals.
>> Translator adapters RS232/RS485 can be purchased for about $25.
>>
>>
>> "Christopher Glaeser" <nospam@xxxxxxxxxx> wrote in message
>> news:fo2dnYYWE7lUR33XnZ2dnUVZ_oGdnZ2d@xxxxxxxxxxxxxxx
>>>> Why USB?  It can be done almost directly with a serial ...
>>> Directly, as in one port?  I need to monitor multiple alarms and need
>>> multiple ports, as in 8 or more.
>>>
>>> Best,
>>> Christopher
>>>
>>>
>>
>>
> Actually, I was talking about simply using a pin on the port.  For a
> serial port, you got two pins, and for a parallel, you got 8-10, IIRC.
> Using direct IO.  You read the port and see the logic state if the pins...
>
> No buss involved..
>
> Another option is a Dallas ds2490 (?) USB to one wire adapter buss (~$25).
> Then, with ds2401's or DS2405's (~$2 each)  you can sense a bunch of
> spots, but the SW to do so is more complex.  I've had my best luck with
> the Linux version of the Dallas SW than the windows version...