Graphical interface and propeller Demo board communicate wireless ???

karakiko

Hello·my dear friends·,
I make a graphical user interface to communicate with the demo propeller board ,it's about to send ASCII strings with a speed of 19200 BPS·throught USB "virtual serial port" , is it possible to make this communication wireless ?maybe bluetooth? or another easy way , range up to 5 meters
Thanks for your idea

Dr_Acula

There are many many solutions. I have a shed full of them! Some are big, some are small, some are expensive, some are less expensive.

After two years of experimentation, I have a network of propeller boards all communicating with these modules www.yishi.net.cn/rf/ProductShow.asp?ID=99

Cost about $25 each. I built some little adaptor boards to change the wire connections to standard 9 pin RS232 connections. That way, you can build a wired connection and then unplug it and replace it with a wireless connection. These modules truly are a replacement for RS232 wires. The only difference is signals can't go both ways at the same time, but the propeller serial objects all have buffers so it is easy to send/listen for response/send etc.

There are also many 'transceiver' modules. They all look slightly different, but for some reason they all come with that little red plastic thingy over the antenna connector. Check you get the antenna with the price, and 'straight' or right angle or even an antenna on a short cable. Prices are all similar. I chose yishi because they are the only ones with a big enough buffer to handle xmodem packets for file transfer. And sooner or later, you want to send a file, right? [noparse]:)[/noparse] Also the yishi ones have very sensitive receivers, -123db which is 1000x more sensitive than some of the -93db $3 'raw rf' modules you can buy. Since the tx power is generally limited to 10mw by law in many countries, increasing the sensitivity of the rx is the main way of increasing range and reliability of transmission.

I'm sure others will have suggestions too.

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www.smarthome.viviti.com/propeller

karakiko

Hello Dr_Acula,
Thanks alot for your reply , so i need 2 of YS-C20U RF modules to connect PC with the propeller[noparse]:o[/noparse]ne in the PC side and one in the Propeller Demo side ???
My application needs one way from PC-->Propeller. The question is how the PC understand this device "virtual serial port " ?

Thanks alot in advance

Dr_Acula

If you are only sending a few bytes then other modules will work ok too. Yishi don't do paypal but my bank happens to have a webpage for online transfers so it was easier than paypal. But there was a $22 fee from my bank. So maybe check with your bank?? Or slightly different modules eg www.microzed.com.au/Rf433.htm

Hmm - these are China and Australia. Are you in the USA? There must be suppliers in the US but I haven't found them yet. I don't think sparkfun sell these.

Depending on shipping costs and bank fees, the best value ones might be here cgi.ebay.com/2-pcs-Wireless-RF-Transceiver-433MHz-FSK-Data-Transfer_W0QQitemZ230447547207QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item35a7be8347

$30 US for two and free shipping. The catch is you need a max232 to convert to RS232 levels to go to the PC, but a max232 is only $1. At the propeller side you might not need any interface but you might need to swap the polarity of the signal in software.

Re virtual serial ports, if you plug in a RS232 to USB device ($3) windows finds it and adds it as a new com port. On my PC com1 and com2 are physical ports, and when I added the USB to serial device there was now a com3. I even added another one and tested them by opening Hyperterminal on com3 and sending data to Teraterm on com4. The propeller software managed to find a propeller on any of these ports automatically.

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www.smarthome.viviti.com/propeller