DS1820 temperature sensor for WL-500gp

Hello,

I've made a DS18S20 -based serial port temperature sensor. I would like to connect it to the usb port on my Asus WL-500gp v2. The temperature sensor works perfectly on the pc connected to a serial port directly, but I can't get it to work with my usb-rs232 serial port adapter. I think the problem with my circuit is that the serial port adapter supplies only 5 volts (like usb does) and a "real" serial port should supply a little bit more..?

I know I could take the power from elsewhere but it would be easier to take it from the serial port.


Has anybody made a similar project, could someone show me a circuit that would work using a usb-serial port adapter?

Here is the schematic: http://elektroniikka.org/thermometer/images/ds9097e.gif

Hope somebody can help..

Quote:

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Originally Posted by skylin3d

Hello,

I've made a DS18S20 -based serial port temperature sensor. I would like to connect it to the usb port on my Asus WL-500gp v2. The temperature sensor works perfectly on the pc connected to a serial port directly, but I can't get it to work with my usb-rs232 serial port adapter. I think the problem with my circuit is that the serial port adapter supplies only 5 volts (like usb does) and a "real" serial port should supply a little bit more..?

I know I could take the power from elsewhere but it would be easier to take it from the serial port.


Has anybody made a similar project, could someone show me a circuit that would work using a usb-serial port adapter?

Here is the schematic: http://elektroniikka.org/thermometer/images/ds9097e.gif

Hope somebody can help..

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try these links (from Google)

http://www.temperaturealert.com/defa...FYU-3godfA10mw

http://www.google.com/search?hl=en&q...earch&aq=f&oq=

http://images.google.com/images?hl=e...-8&sa=N&tab=wi

Quote:

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Originally Posted by darius

try these links (from Google)

http://www.temperaturealert.com/defa...FYU-3godfA10mw

http://www.google.com/search?hl=en&q...earch&aq=f&oq=

http://images.google.com/images?hl=e...-8&sa=N&tab=wi

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rofl darius:p
"only 129.99$":o
isn't that a bit over an average budget range?;)

anyway... I hear serial port
http://wl500g.info/showthread.php?t=18561
raas managed to do something with a temperature sensor:)

Quote:

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Originally Posted by wpte

anyway... I hear serial port
http://wl500g.info/showthread.php?t=18561
raas managed to do something with a temperature sensor:)

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hehe... :D wpte, didn't you post a nifty usb temperature sensor (plus some more) as last reply on that topic.. maybe that woul do the job for skylin3ed
My setup will def. work, but I think it's a bit overkill if you only want temperature.. (however.. if you start with these kind of things one would like to have some room for expansion and other input signals, and maybe even output signals.. )

Well I would like to use the DS1820 because it's really cheap, about 6-7$ for the whole circuit, and it suits my need perfectly..

Here is a similar project as the one I would like to build: http://wl500g.info/showthread.php?t=7572


I think the problem could be that the circuit is originally made for a real serial port, and I'm using a pl2303 -based usb-serial port adapter which doesn't supply as many volts as a real serial port..

Hello,

I'm not sure if you still need this, but instead of sticking to 1-Wire serial adaper, better buy USB to 1-Wire Adapter (DS9490R ).
I have 6 temperature sensors(DS18B20) and one USB to 1-Wire Adapter (DS9490R ). The sensors are connected to DS9490R , and DS9490R is plugged into the USB port of the router. Cost of DS9490R is around 15 euro, depending on the country.
If you use Oleg's firmware you can use Digitemp package to read the sensors form the 1-wire bus. It is very simple.
If you use openwrt you can use also owfs pakage, which seems to be better.

I have now finally got this to work using this usb -> rs232 adapter. I was previously using a cheaper one which did not have the required usb to serial voltage conversion chip inside, but this one has it and digitemp now works perfectly! So the problem was that the sensor didn't get enough voltage.

Here is a short howto which should help a bit: http://wl500g.info/showpost.php?p=57434&postcount=4

You also need to load the following modules to get the usb to serial adapter working:

Code:

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insmod usbserial
insmod pl2303

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