Wireless rs232 options?

[shoneill]

Hi Everyone,

I'm looking for the possibility to implement a transparent RS-232 to Wireless conversion. In our Lab, we have many different instruments which communicate via RS-232. Depending on what measurements are currently being done, we have to move the instruments around to connect them all to one PC, and the resulting hassle and cable salad is getting quite annoying.

I was thinking of fitting many of the instruments with an RS-232 to wireless (Either 802.X or bluetooth, I don't really care - Security isn't really an issue either) so that no more cables need be connected.

However, in order for the existing software to run unchanged, I need a wireless transmitter/receiver per COM port on each computer (adds up to a total of around 2
4 units each Transmitter/receiver).

Am I being a bit blue-eyed in thinking that this should be realisable on a moderate budget? It's not a mission-critical implementation, just a (very welcome) luxury.

I looked at the NI RS-232 to Ethernet solutions, thinking that I could then slap on an Ethernet/Wireless unit but this is already quite expensive.

Anyone got any ideas?

Thanks

Shane.

[Methis Elddir]

On Fri, 19 Mar 2004 04:36:21 -0600, shoneill wrote:

[snip]

> I looked at the NI RS-232 to Ethernet solutions, thinking that I could
> then slap on an Ethernet/Wireless unit but this is already quite
> expensive.

I agree with your last statement. Using a converter would be the easiest
but possibly quite expensive.

Go to the B&B Electronics site. They have more options than NI and they
are cheaper. Look at the Multi-Port Serial Server section here:
http://www.bb-elec.com/productlist.asp?Dept_id=99

They also have a wireless model (70001958) at the bottom of the page. 4
ports for $677.95. But if you need 24, that's over $4,000. Hmm... After
looking around, I don't think there is an inexpensive wireless solution.
It seems cheaper to keep it all wired
or just partially wired.

I can think of two possible solutions:
1) - 24 RS232-to-RS485 converters at $60/each
- one RS485-to-ethernet converter for $150
- cost: ~$1500 (w/o cables)

2) - one monster, 24 or 32 port serial port card (Rocketport)
- one junk PC w/ethernet adapter that the card goes into
- PC acts as a serial port server that other PCs can access from the
network. need to write a server program.
- cost: varies depending on where you buy it. I just looked on eBay
and found a 32 port ISA card for $50

Option 2 certainly looks like the cheapest but you have to factor in the
cost of building your own server software; however, I bet there's already
an open source solution. Neither option really gets rid of your cable
problems though.

Hope you don't mind my rambling, I just find this stuff interesting.

[shoneill]

I don't mind your rambling at all.

I think I'll have to pass on the idea for the time being. The whole idea was to have a modular system, which would really have required that EACH com port have it's own serial-wireless connection. This would mean 24 RS-232-Wireless converters with a single "access point" on the computer. That way the instruments can be moved around (not necessarily all together - hence my modularity requirement) and connected together in any way while still maintaining the connection to the host computer.

Oh well, who knows what the future brings.....

Cheers

shane.

[Methis Elddir]

On Fri, 02 Apr 2004 02:25:19 -0600, shoneill wrote:

> I don't mind your rambling at all.
>
> I think I'll have to pass on the idea for the time being. The whole idea
> was to have a modular system, which would really have required that EACH
> com port have it's own serial-wireless connection. This would mean 24
> RS-232-Wireless converters with a single "access point" on the computer.
> That way the instruments can be moved around (not necessarily all together
> - hence my modularity requirement) and connected together in any way while
> still maintaining the connection to the host computer.
>
> Oh well, who knows what the future brings.....
>
> Cheers
>
> shane.

Yeah, that would be a very expensive modification. I'm sure the prices

will come down in a year. Good luck.