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When using multimeter to measure VIN-GND or VCC-GND voltage, make sure you are measuring in DC, not AC. On a standard multimeter, DC voltage is marked as a V with a flat line above it; AC voltage is marked as a V with a curvy line above it. If VIN-GND is 5V, that’s correct. You said VCC-GND is 4V and 7V by your two meters, that seems to suggest a problem. VCC-GND should be 3.3V.
Going back to the instructions:
http://rayshobby.net/blog/?page_id=8074#part2
did you check the resistance between VIN-GND and VCC-GND? Are they within acceptable range?Also, to isolate the problem, I suggest that you power the controller with a USB cable first, and check voltage, then move on to use sprinkler transformer. This can help diagnose whether the problem is in the 5V to 3.3V conversion and beyond, or it’s in 24VAC to 5VDC conversion.
OSPi takes four GPIOs (these cannot be shared with other devices), and the I2C pins (these can be shared with other I2C devices). This diagram shows which pins are taken by OSPi:
http://rayshobby.net/wordpress/wp-content/uploads/2013/02/ospi_diagram_connection.jpg
The other pins are free and you can use any of them.Many AC transformers are unregulated. 55V seems really high. Are you sure you are measuring AC voltage, not DC? If you happen to use the DC level on your multimeter to measure AC, you will be surprised to find some strange result. 30V AC should be ok.
Where are you located? If you are in the US, you can buy sprinkler transformers from Amazon.com or at local home improvement stores.
Sorry, I didn’t notice you mentioned sub-second on-times: this is currently not supported. The minimum run time is 1 second, but this can certainly be modified in software to support sub-second run time.
The zone expansion board only consists of a shift register and eight triacs, and does not have a microcontroller or Ethernet controller in it. So it would not be possible to have the main controller talk to expansion board through wireless. You may be able to connected them wired with a RJ45 Ethernet cable (you will need to figure out the wiring). But this hasn’t been tested over a long distance so you may need to experiment with it to see if this is reliable.
Is it possible for you to set up port forwarding so I can take a look? If not, can you send me the list of programs (or take a screen shot) so I can try to replicate your programs and check what causes the preview to hang?
The water level (or now called the percentage of watering) is available as a javascript variable (wl) when you access the homepage, or the view options /vo page.
If you have OpenSprinkler 2.0 and have upgraded your firmware to 2.0.3, the water level variable is also available through the json page /jo
I think what you described is already supported by the interval program, which is available on all of OpenSprinkler (microcontroller-based), OSPi, and OSBo.
This has been brought up more than once in the past. I suggest doing so only if you have a good idea how the other controller works internally. The reason is that not all controllers work in the same way. On OpenSprinkler, one wire of 24VAC is tied to the circuit ground, and the other wire is common. For each solenoid, one wire is tied to common, and the other is tied to a triac. Switching the solenoid is done by turning on the triac thus completing the circuit. On other controllers, the circuit ground may be the common wire; also many controllers use an isolated design. Without knowing the underpinnings, it’s difficult to tell whether a SPDT to switch between the common wire is sufficient to get them running safely in parallel.
Manual operation on the controller was a feature in the early versions of OpenSprinkler firmware (firmware 1.5) but it has been removed partly to save program memory space, partly because web-based operation is more intuitive and useful. I do hear comments from users that they’d still like manual operation on the controller, because this would be useful for their landscapers who are not given access to the wifi network. So I am still considering adding it.
Hmm, this is odd. You have firmware 1.8.3, right? I’ve tested 1.8.3 and I don’t think it’s limited to 8. Back to the question I asked earlier: when you click on the ‘Programs’ button which will print out the list of programs, does the browser hang? If not, it’s still likely to be a browser issue. The code for showing programs and previewing programs outputs the same data, except that they refer to different javascripts, one is to list the programs in a table form, the other is to render the programs in graphics form.
1) You are probably just getting stray voltage because there is no load connected to the port. If you want to do a quick test without an actual solenoid, you can connect an LED with a 4.7K resistor (or any resistor between 1K and 10K) in series between the COM port and any station port you want to test. The LED should light up when the station is on.
2) If you search for sprinkler valve you will find plenty of choices. For example:
http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=sprinkler+valve&rh=i%3Aaps%2Ck%3Asprinkler+valve
I’ve mostly used Orbit inline valves (you can choose 1inch or 3/4 inch depending on your pipe size). These are also available at homedepot and lowes stores, so you can go to a store to grab one. If you need to connect these valves to garden hose, you can get NPT to GHT adapters, which are also available at stores.Also check the ‘sprinkler valves’ section of the FAQ page to find other information: http://rayshobby.net/?page_id=207#sprinkler_valves
On the OpenSprinkler circuit, one wire from 24VAC is tied to the circuit ground, the other is called the common (COM) wire. Each solenoid has one wire that’s connected to the common wire, the other tied to its corresponding triac’s T2 terminal. And you are right that the triac’s T1 terminal is connected to ground. When the triac is turned on (i.e. gate to ground voltage above threshold), the channel between T1 and T2 is open, thus completing the circuit (24VAC common -> solenoid -> triac -> 24VAC ground).
The resistor value is 300 ohm. But anywhere between 200 to 330 ohm should be fine. According to the triac’s datasheet, the gate to ground voltage drop is about 1 to 1.3V, and you need at least 5 to 7 mA of gate holding current for triac to remain open. So assuming the microcontroller outputs a voltage of Vcc (in the case of OpenSprinkler, Vcc = 3.3V), you can calculate the necessary resistor value. For example, (3.3V – 1V) / 7mA = 328.6 ohm.
Oops, I have forgotten to check in firmware 2.0.3 source code. Just did it a minute ago. The twi issue was because some old Wire.cpp / Wire.h files were left in the folder. They are now removed. Check to see if the newly checked in files work. Also if you have hardware 2.1 make sure you also update your Arduino/hardware/aopensprinkler/boards.txt file as it contains the board profile for 2.1 (runs at 12MHz with USbasp bootloader, vs. 2.0 running at 8MHz with USBintyISP programmer).
You are right, systemctl is not part of Ubuntu. I haven’t done much research on this and I am tempted to think you can create a init.d or use rc.local script to perform what you were able to do manually. If you check the Adafruit tutorial on RTC for Raspberry Pi:
http://learn.adafruit.com/adding-a-real-time-clock-to-raspberry-pi/set-rtc-time
towards the end there are descriptions about adding a few lines in rc.local to read from RTC automatically on startup. I will check if this can be done on the Bone with Ubuntu.The physical size does not matter. What matters is the electric spec. For example, if the valve draws 200mA of current, make sure the transistor or mosfet you are using can supply that amount of current. Since this is DC valve, you can measure the resistance on the two wires and divide 12V by the resistance. That will give you an idea of the operating current.
1) Regarding downgrading to 2.0.0, the issue was because you used ‘-p m328p’ in the command. It should be ‘-p m644’ because OpenSprinkler 2.0 uses ATmega644 microcontroller, not mega328.
2) Regarding microSD card problem, how did you format the SD card? I’ve had issues when formatting the card in Linux. It should be formatted to FAT16. Somehow when I formatted it in Linux it wasn’t recognizable, but it was fine when formatted in Windows. I will investigate the issue later.
3) I’ve just released firmware 2.0.3 in Github. Please my next post for details. Basically 2.0.3 uses Javascripts stored at rayshobby.net by default, and provides an option to change the Javascript url if you need. For example, if you want to host it locally on the controller, you can copy files to a microSD card, pop it in, and change the Javascript url to . (i.e. a dot). For details please see the next post.
Can you provide some details about your setup? For example, what type of AC transformer do you have? Are you using a WiFi dongle or wired Ethernet connection? Have you set up a sprinkler program and if so does it open multiple valves at the same time?
One likely cause for the rebooting is that the voltage may be dropping below an acceptable level. For example, if the AC transformer’s current rating is not sufficient, or if multiple valves open at the same time that exceeds the capability of the transformer, or if for some reason the RPi is drawing a large amount of current from OSPi. Knowing your setup will help diagnose the cause.
Regarding the screws and support pillars, sorry about that. Those should be included in the kit in a blue plastic bag. You can send an email to [email protected] with your address and we will send it to you. Thanks.
Sorry I got confused and didn’t notice this is referring to OSPi. The current OSPi version (v1.3) does not have MOV or TVS installed on the board, so in addition to replacing triacs with transistors, you also need to add flyback diodes.
I thought the OSBo image is configured to use RTC . I could be wrong since the RTC part has not been thoroughly tested. Note that the RTC initially needs to be set with the current time. Otherwise it will always go back to 2000 Jan 1. Once set, the clock will start running and it should keep up with current time.
There have been some discussions on the forum about interfacing with DC valves. For example, take a look at this thread:
viewtopic.php?f=9&t=214&hilit=dc+relayPretty much the only change is to replace triacs (i.e. AC transistors) with transistors like 2N3904 or mosfets like BS170. The selection has to depend on the current rating of your DC valves. The issue with triac is that it needs a zero-crossing in the voltage to turn off, so it’s only suitable for AC power. Since DC power does not have zero-crossing, once turned on, the triac will not turn off until you cut off power. The thread above also mentioned flyback diodes. From OpenSprinkler 2.1, there are either MOVs or TVS on the board, which can act for flyback voltage protection, so you don’t need to add separate flyback diodes any more.
The enclosure is not waterproof and to use it outdoors you must put it in a box or in other protected manner. There are several choices for a water-proof enclosure. For example, this one from amazon:
http://www.amazon.com/Orbit-57095-Sprinkler-Weather-Resistant-Outdoor-Mounted/dp/B000VYGMF2
is sufficiently large to fit the controller, transformer, and wifi adapter. You can also search ‘sprinkler enclosure’ or ‘sprinkler case’ to find other similar products.
