From Hackaday: Single chip usb temperature sensor.

Have not tested this, so try at your own risk.




From Hackaday (http://hackaday.io/project/6258) Single chip  usb temperature sensor.
Description
I  (the Hackaday author) created this project because I wanted to learn about PIC microcontrollers and the USB protocol. I also wanted to see how simple I could make a USB device. I've gotten it down to two components: a PIC16F1455 microcontroller and the USB connector. The microcontroller acts as a USB serial device and will send the temperature as an ASCII string once per second.
Details
The PIC16F1455 is a relatively new microcontroller that can do USB without an external crystal. It also has internal pull-up resistors for the USB data lines. These things mean no extra hardware is necessary for USB communication.
I needed something useful to send over USB and I noticed that the PIC16F1455 has a Temperature Indicator Module. This peripheral will let you read the operating temperature of the silicon die over the ADC. It's not terribly accurate, but the silicon die temperature will be about equal to the outside temperature.

I carefully soldered a male USB Type A connector to the PIC16F1455's Vdd, Vss, D+, and D- pins. Then, using the M-Stack USB Stack from Signal 11, I wrote a program to enumerate the PIC16F1455 as a USB CDC serial device and send the temperature in ADC counts as an ASCII string at 1 Hz.
From the computer side, it's easy to connect to the USB temperature data logger like any other serial device, parse the incoming strings, and save the data to a file with a timestamp.
The last step is to map the ADC counts to a temperature scale. Microchip has an application note AN1333 with some equations. However, for a constant Vdd, the scale is pretty linear so it's easiest to record the ADC count at two known temperatures and interpolate between them.

Looks pretty straight forward.

Some code links:

 https://github.com/mogenson/USBTempLogger

 https://github.com/signal11/m-stack

Comments

Post a Comment

Popular posts from this blog

Guiless?

Image
You actually can do a minimal windowing from the command line in Linux with dvtm. Dvtm is excellent for low end machines where graphics are not a priority. In the picture shown we have a working clock, SC a spreadsheet that you can easily export data to your favorite desktop spreadsheet such as Libreoffice, Links2 a web browser pointed to www.google.com, and finally nano a pretty decent basic text editor. I prefer vim, but nano has more of a user interface. Cheatsheet: `dvtm` is one simple, easy-to-use terminal multiplexer. Commonly used Options:     -v         prints version information to standard output, then exits.         -m <mod>   set default modifier at runtime.         [cmd...]   Execute cmd after dvtm is started. KeyBoard Shortcuts:     Mod    Each keybinding begins with Mod which defaults to ^g but can  be               changed in config.h or with the -m command line option.                       Mod-c  Create a new shell window.            Mod-x  Cl
Read more

Web.com and Network Solutions, the Walmart of the internet.

Web.com bought Network Solutions last month, and also has bought Register.com . Web.com picked up Network Solutions for $405M plus some stock. I have been using an e-commerce package form Network Solution for two years. I wouldn’t have noticed the buy out as the Network Solutions site has not changed. A couple of weeks ago I noticed that Network Solutions was offering some new products such as Gorilla Online Marketing . Soon after that we received a sales call about Gorilla Online Marketing from Network Solutions. When I returned the call the phone was answered by Register.com, I was confused at first but quickly found out about the buy outs. They seem like a good fit, they all target the same types of small to medium size businesses. Network Solution has always had great customer support in my opinion. Their sales people are a little irritating sometimes but they beat the heck out of GoDaddy.com and Comodo.com and you can’t beat the prices. If you can beat the prices ask them for a
Read more

MSOffice vs Libreoffice

Image
From https://wiki.documentfoundation.org/Feature_Comparison:_LibreOffice_-_Microsoft_Office Contents 1 Introduction 2 General office suite: LibreOffice vs. Microsoft Office 3 Word processors: LibreOffice Writer vs. Microsoft Word 4 Spreadsheet applications: LibreOffice Calc vs. Microsoft Excel 5 Presentation software: LibreOffice Impress vs. Microsoft Powerpoint 6 Database program: LibreOffice Base vs. Microsoft Access 7 Extensions: LibreOffice extensions adding outstanding features to LibreOffice 8 See also Introduction This page compares the features of LibreOffice 5.0.0 ( download ) and Microsoft Office 2013 . It separates major and minor feature differences and also includes notes on LibreOffice extensions. The comparison highlights differences and therefore does not display any features which are present in both office suites. The feature comparison table is continuously being updated and is work in progress It is a compilation by users and no
Read more