- Blog entry posted in 'Electronics and Other Ramblings...', March 04, 2012.
I’ve been looking at a simple way I can “play” and “monitor” several gadgets on my router/printer/etc room through any pc on the house. I looked at using wireless modules of different frequencies/technologies (ISM/433MHz, Zigbee, …); all would require specific hardware at each of the PCs … not quite what I had in mind. Around came two things which seemed to be “better”: The Wifly module from Roving Networks (e.g. Wifi Garage Door Opener) and the WIZ110SR module Wiznet. The Wifly module looked pretty cool, and the garage door application example I looked through was nothing short of cool. However although I am quite capable with hardware, I am not quite savvy with Ethernet stuff (you know protocols, etc). So when I looked at the WIZ110SR and saw that I could do simple RS232-to-Ethernet (telnet) communication with it I figure I could possibly start with that.
So I order one along with a +5VDC wall-wart. Here’s how it went…
Remember I mentioned I’m no expert at Ethernet stuff - I can speak SPI, CAN, I2C… but for Ethernet all I know is to plug it and play. So that’s exactly what I did (the manual is not too great on this respect). You connect the module to the PC (straight) no router or anything else … and of course nothing works. It shouldn’t, not unless you setup the PC’s port to the same subnet and all that cool stuff. This much I expected; but I would have also expected the manual to detail what the default configuration of the module is (I can’t say I found it). So I proceeded to connect the module to the router (to allow it to assign an IP address to the module) … I’m sure if I knew what I was doing it would’ve worked; but I was not getting there fast enough. No matter what the Wiznet’s Configuratio Utility would not “discover” the module.
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So I scoured the web for examples, faqs, etc … and I found out that the serial port, even though would not allow configuration until enabled with the config utility, would report the initial/default state. Of course I wasn’t sure what the serial port was configured (again, the manual doesn’t quite state that). So I looked at a few pictures and all seemed to say 57600-8-N-1 … yesss that’s what I was looking for. Also the connection SW1 will re-start the module. Connect the serial port to the PC, set for 57600-8-N-1 and default configuration is at your fingertips once the module powers-up.
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Next, use this information to configure the PC’s Ethernet port. Connect the module to the PC through Ethernet and use the configuration utility to search for the module … using the “Direct IP Search”.
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Now you can change the RS232 configuration if desired…
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And better yet, enable configuration through the RS232 port…
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This is probably the simplest stuff you can do with this. But now know how to configure it and communicate between RS232 and Ethernet (through Telnet).
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Not sure yet where this will go, but given some time I’m sure it can be put to good use.