Connect Many basic stamps to one PC

Archiver

I want to connect my PC to many basic stamp 2e with serial communication RS-232. I have read the article about make network using BS1. In that article only connect the Basic Stamp directly to the PC with an additional componen. Can I do this in the Basic Stamps 2e. Before that, I suggested to use RS-485 driver to make the network like the example in the Basic Stamps magazine. But the example using different Basic Stamps, not Basic Stamp 2e ( I only have Basic Stamps 2e)

Thanks for any comment.

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Archiver

At 08:11 PM 6/10/2004 -0700, you wrote:
>I want to connect my PC to many basic stamp 2e with serial communication
>RS-232. I have read the article about make network using BS1. In that
>article only connect the Basic Stamp directly to the PC with an
>additional componen. Can I do this in the Basic Stamps 2e. Before that, I
>suggested to use RS-485 driver to make the network like the example in the
>Basic Stamps magazine. But the example using different Basic Stamps, not
>Basic Stamp 2e ( I only have Basic Stamps 2e)
>
>Thanks for any comment.


The BS1 network example should work with the BS2, but keep in mind that you
will need to convert the code so that
it will work on the BS2. The main Difference between RS232 and RS485 is
that one is voltage driven and the other
is current driven. The advantage of RS485 is that you can cover greater
distances than you can with RS232 because
external interferences can be minimized within the current loop. An
advantage of RS232 is that it is much easier
to implement with less component overhead than RS485.



Another Approach aside from the BS1 network example:

If you must use RS232 or RS485, then the Stamp that talks to the PC should
be considered a 'Master' while ALL of
the other Stamps would be considered a 'Slave'. Setup a communication
protocol similar to I2C between the Stamps
where each 'Slave' Stamp has a unique address that it must receive from the
'Master' Stamp before it responds.
Otherwise, if RS232 or RS485 is not necessary, then you can still use an
I2C derivative, only the PC would act as
the 'Master' while ALL of the Stamps would act as 'Slaves'.

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