Posts tagged arduino
Well I am still making progress with my analog alarm/monitor box, but really still need to come up with a better name for it! If anyone has any suggestions, please shoot!
I just finished the board design (I hope it is correct) and ordered a few boards, I should have them just after valentines. All the other components I already have in stock, so I should hopefully be able to offer a few kits for any of you that would like to have one of these yourself.
The software development is also going steady. I finished last weekend the configuration software (webbased), fully based on ajax. You can setup for each meter what object you want to meter (VM, Host, ResourcePool, Cluster, Datacenter) and then select any of the available counters for that object. A few are percentage based, so the meter can display 0% to 100%, but you can also have absolute numbers displayed, as you can define in the config software the min and max value.
I guess before I receive the circuit boards I really need to finish the casing, as I have not done much work on that. Hopefully can make some progress on that coming weekend. My current prototype just have a faceplate. In the end I will design 2 versions; A 4 meter version and a 6 meter version.
To be continued….
As I received many positive reactions on my Analog Alarm Box to monitor your VMware vSphere environment, I decided for the first “finalized” product to not include the split-flip display, as I still need to work out a lot of things to be able to “mass” produce it. The slim box will have 4 analog meters and you will be able to decide yourself what each meter displays. Like 4x the CPU usage of 4 different clusters or the CPU and Memory Usage of 2 clusters, storage consumption, or what ever.
I am adding a 2 line 16 chars LCD display in the box, that can show the names of the meters that are being displayed and can also display alarm notifications. The box will get a buzzer, for when an alarm condition is met. You will be able to configure and setup the box using the build-in webserver.
I will make easy kits that people will be able to assemble that will contain everything but the Raspberry PI board, including a breakout board will all the electronics that can just be put on the header pins or the Raspberry PI, 4x the analog meters, the LCD display, buttons and the wooden box itself.
I know this is supposed to be a weekend project, but I had some spare time on my Thursday evening So here an update on my vSphere Alarm Box.
I received my analog panel meters this week. Instead of them displaying 0 to 5v I created some new face plates for them using my automatic paper cutter so they can display CPU and Memory consumption. These meters are very easy to control by using a PWM signal, but the challenge is that the Raspberry PI only has one PWM port. So I decided I want to use an arduino for this. Making the Raspberry PI talk to the arduino is fairly straight foward. I am using I2C, but as the arduino uses 5v for its logic circuits and the Raspberry 3.3v I had to build a small level shifter to allow both both safely to communicate over I2C.
Everything now connected hardware wise, now I just had to make the meters work, displaying the right information from VC. I am writing my code in PHP and already had last weekend written the PHP code to use the QueryPerf API call to retrieve the last 5 minute average for CPU and memory of my cluster. But PHP does not allow me to send I2C calls, so I had to write an extension module for PHP to enable me to do this. As I never had written an PHP module, thanks to google, this did not take too long
So there it is.. IT IS WORKING Every minute Raspberry PI uses QueryPerf to retrieve information from VC. Using my PHP I2C extension it sends an I2C call, via the level shifter to my arduino. The arduino uses the value received via I2C to set the PWM for the specific pins and tha dah… working