Its been a while since I posted any news, so I thought I give you a quick update. I've been very active in my "day" job and other activities, so I haven't had much time to work on weather projects. That did change recently: Rabbit Semiconductor has a temporary price reduction on the WiFi-enabled Rabbit 4000 development board. I couldn't resist!
One of my desires is to go completely wireless. I've tried various methods, including the Maxstream Zigbee RS-232 modem with various degrees of success. The Rabbit WiFi board, along with a solar panel and a battery looks to be promising. The only item you'll need inside is a WiFi router. I've ported the Dallas/Maxim public domain 1-Wire C library to work on the Rabbit 4000 (see below). So far I have a simple version of the 1-Wire weather software and a web server running on the Rabbit. I'm now trying to wedge in the Weather Underground code, but I'm having memory limitations. I'll post the code here when I get it working.

If you havn't had a chance to check out the discussion forum, there are now several hundred posts. Go take a look.

Tim

A beta version of Dallas/Maxim's 1-Wire Public Domain C library ported to run on a Rabbit 4000 is now available. The code is written to run on a Rabbit 4000 develoment board with standard RS-232 ports. There is no documentation yet, so it isn't for beginners. As noted above, I'm using it on the Rabbit 4000 WiFi development baord for a truly wireless weather station. The 1-Wire is connected using a standard DS9097U serial to 1-Wire adapter connected to serial port C on the dev board. The RS-232 handshake lines (RTS & DTR a.k.a Serial port D) supply the power on the stock serial cable. The library takes up quite a bit of memory, but provides a full set of 1-Wire commands.

Download the library and example code for the DS18S20, DS2423, DS2438, and DS2450 Here

An update to ETWS has been posted in the downloads section. Version 1.0.7 fixed a couple of bugs, but most importantly, now has separate versions for Mac and Windows. Trying to combine the two created several issues with getting it to run properly on both platforms, so I went ahead and split them.

The Weather Toys Discussion Forum is now online. There are forum for hardware, software, book updates, and general 1-Wire Weather topics. Got an idea for a new 1-Wire sensor? Post it here. Got a question about SimpleWeather? Ask it here. This discussion forum is for all 1-Wire weather enthusisants, whether you've read Weather Toys or not.

As part of the change, the Weather Toys Blog has now been renamed News. The software updates and book corrections have been move to the forum so they're easier to find and you can post your comments. The News page will now contain information updates about the world of 1-Wire Weather along with Weather Toys information.

Many of you have requested information on using a 1-Wire Hub with the Weather Toys projects. I have finally had some time to put together a simple example of using a hub with SimpleWeather. Also included is a modified OneWireLister that can find your 1-Wire devices connected to a hub. Download the file HubExample.zip in the Downloads section. For more information, see the ReadMe.txt file in the download.

While working on a weather project, I happened to notice that the Radio Shack twisted pair cable was manufactured incorrectly. The RS 279-460 cable (referred to as the "short-length cable" on page 63) should have the red-green and yellow-black pairs twisted. The cable I recently purchased had the red-black and green-yellow pairs twisted. You can still use the cable, but you'll have to either use the red-black or green-yellow pair for your 1-Wire bus. The cable pictured on the right is correct.

Congress has passed a bill mandating changes in Daylight Savings Time for the US starting March 2007. This could have some impact on your weather code if you are using a time zone different than the default. Both SimpleWeather and ETWS use the default time zone, so the time is based on your computer's time. Both Apple and Microsoft have issued updates to the OS, so the change will most likely not affect you. But, like the Y2K concern, time will tell. If you do use time zones (part of the Calendar class), check out the Sun's article "U.S. Daylight Saving Time Changes in 2007" at http://java.sun.com/developer/technicalArticles/Intl/USDST/ to learn more .

Maxim has not distributed a driver for the DS9490 USB Adapter for Mac OS X. Maxim Engineer Scott Hughes has developed his own solution using the libusb open source library. You can get Scott's code at globalreset.org. Click on the Mac OS X link. You'll need to install libusb and then modify your SimpleWeather code to use his Java library.
PLEASE NOTE that at this time I can't offer any support for the Mac using the USB driver. My installation seems to cause the USB bus to freeze requiring a reboot. If your installation works or you have any suggestions, please let me know.

Sun has released Java version 6. Early tests indicate that both SimpleWeather and ETWS are compatible with Java 6. As a result of the update, Sun has changed their web site, and most of the book's links to the website are no longer valid. Both the JDK and Documentation can be currently found at http://java.sun.com/javase/downloads/index.jsp. You'll also find a link to the older versions of Java.
On this website's Downloads page you will find both the Java JDK Version 5 and the documentation. Unless you need a newer version of Java, I suggest you start out with these so your project will match the book.

The Weather Underground recently released it's RapidFire weather service. It supports posting data to WU as fast as every 5 seconds, and you can embed a really cool Flash-based "widget" in your web page to display the data. The protocol to post the data is nearly identical to the one used in Chapter 13. If you're interested in playing with this, you can find the info needed to modify SimpleWeather at http://wiki.wunderground.com/index.php/PWS_-_Upload_Protocol
Here's a sample web site using RapidFire: http://www.wunderground.com/weatherstation/WXDailyHistory.asp?ID=KORSWEET1

Several readers have requested an update on using the USB adapter. Dallas/Maxim now provides a driver for Windows 2000 & XP. Here's how to use it with SimpleWeather:

• Installing the Drivers:
  1. Download the 1-Wire Driver Version 4.0 package from http://www.maxim-ic.com/products/ibutton/software/tmex/index.cfm
  2. Make sure the 1-Wire USB Adapter is unplugged
  3. Start the installer
  4. De-select the two custom options and click Next and follow the on-screen instructions
  5. When prompted, install the 1-Wire USB Adapter and let Windows find the driver
  6. Select the DS9490 in the Port Selection dialog at port USB1
  7. Click OK
• Verify Installation:
  1. Click Start -> Programs -> 1-Wire Drivers -> OneWireViewer.htm
  2. Follow the instructions to run the OneWireViewer
  3. If OneWireViewer works OK, your drivers are loaded successfully
• Modifying SimpleWeather
  1. Change ONE_WIRE_SERIAL_PORT = "USB1"
  2. Change ADAPTER_TYPE = "(DS9490)"

SimpleWeather should compile and run with the new adapter. I'm not sure why, but the DS9490 needed the parens around the name.

UPDATE 1/6/07: I've received emails that that many of you can't detect the DS9490 after following these instructions. After many frustrating hours, it seems that "some" XP installations need curly braces for the adapter name in step 2 of modifying SimpleWeather instead of parentheses.

The Bonus Code download now includes sample code to incorporate AAG’s TAI8570 Pressure Sensor in SimpleWeather. If you have the TAI8570, you can now use it along with the Weather Toys book.

Seems like I got some of the part numbers mixed up. The standard 1-Wire temperature sensor is the DS18S20, not the DS18B20 as mentioned (inconsistently) in Chapters 3 and 5. The ‘B20 has selectable resolution (9 to 12 bits) and includes a thermostat function. It also costs a bit more. The ‘S20 is what is used in the WS-1 and Hobby-Boards modules. Both parts will work fine, but there are some minors changes to the code:

• The DS18B20 is Family Code 28
• The 1-Wire container should be OneWireContainer28
• The RESOLUTION_MAXIMUM class field isn’t supported, instead use RESOLUTION_12_BIT.
• Since they each use a different container class, the ‘B20s can’t be mixed with ‘S20s using the same class.

The sample code for the solar sensor (located in the bonus code folder) provides an drop-in replacement class for use with the DS18B20.