need transeivers for system development

[T. Rooks]

Hello,

Please be gentle. This is my first time;) .

I am a retired computer/medical electronics/electromechanical device field engineer.

A friend got me interested in developing an idea he had. It involves having various separate units performing precise high speed operations in a time and security critical network.

I have developed several modules and have them working as intended in a 'hard wired' ring topology configuration. What I now need is to get them converted to wireless using as small packages as possible to get no less than 100 meters range in the outdoors. They must also have an operating temperature range of -50 to +85 C. They will spend most of the time waiting for very short transmissions and will respond with very short transmissions.

I am prepared to develop my own protocols for them to sync up and accept commands/data to and from each other as I already have a rudimentary system doing that task. However I would not mind modules that have embedded 16/32 bit processors if I can get documentation and be able to use Basic or C programming and if it can add an extra level of security with minimal time overhead.

Any and all recommendations, suggestions or ideas will be greatly appreciated and acknowledged.

Thanking all in advance for your help,

Tim

[T. Rooks]

Nguyen,

Thank you for the additional info.

I like the idea of having processing power as pat of the Tx/Rcv units. I will have to study the specs for the unit and determine if other factors such as additional I/O and memory will suite my needs. Also Bluetooth is something new to me and I have no clue about how it operates or what it is capable of. Time constraints dictate that I stick with Basic programming if at all possible.

I am having to take some time away from my project to deal with a personal family matter and am not sure how long it will be before I can get back to working on it.

Thanks again,

Tim

You can teach an old dog a new trick but he might not remember it for very long.

[T. Rooks]

Nguyen,

A follow up.

The 51822 is quite impressive.

I will not be able to use it though. I simply refuse to get off into Bluetooth.

There is way too much of it in all kinds of guises out there. It would not do for one use of it I did not know of to show up at a product demonstration and wreak havoc with my system. There are also other considerations of at least not making it easy for others to monitor and figure out things about my system.

(Most do not realize the implications of all those street level photos on g-o-o-g-l-e earth. Every neighborhood was also swept to identify whatever types of wireless systems were in that neighborhood and tie them to specific addresses.)

I will likely go with something like the 24L01 if I can find one that allows for network broadcast to all units like what was available on the XBee modules. Otherwise I will be stuck with a control unit with a lot of antennas sticking out of it with transceivers and processors for each of them.

I am certain I can do what is needed for the programming using an Arduino since it has been around a good while and there should be some code examples for me to study and adapt to my needs.

One thing about not having a lot of money to spend is that you have lots of time to figure out how to best spend the little money you have. ]8-(

Tim

[Nguyen Hoan Hoang]

Ok, if you prefer Zigbee then Atmel has MCU with Zigbee inside. They have both AVR & ARM core version. TI also has ARM Zigbee I think. Freescale also have something. Zigbee Stack software from Atmel is bad coding. TI is better, Freescale don't know. Atmel has free software development tools. Any ARM development can be done with Eclipse and GCC so it's also can be free. There are also Wifi solutions or just plain RF modem. :)

[T. Rooks]

Thanks for all the advise.

I have decided to go with RS232 to RF transceivers.

I already have several MCUs to program in Basic for my private communications scheme.

Fare Thee Well,

Tim