Tagged: I2C LCD
June 27, 2015 at 6:05 pm #38773
I see there have been some people start projects for LCD and push buttons which is what I want so people used to standard sprinkler controllers – techs, future home owner, etc can operate it. I don’t care about the case size – I can put it in a larger case. The software is the issue for me as I am just a code hacker – I can do minor mods but hard for me to write much from scratch. I found this:
but I didn’t find any links to the code.
and I see the latest version of code supports an I2C LCD (not sure about buttons).
What do I need to put together this? It would be great to have a web page for control but also a local status display/control.
another question – any issues with running it without network access?June 27, 2015 at 10:22 pm #38778
The latest firmware has added support for I2C LCD for the microcontroller-based OpenSprinkler. We haven’t added the same support for OSPi yet. But on Github there is a pull request that has implemented I2C LCD for OSPi and OSBo:
I haven’t had time to carefully check the pull request, but you can feel free to experiment with denisfrench’s code provided there.
You can host the web UI on RPi itself. We don’t include this in the preconfigured SD card because we make frequent changes to the UI and to get the latest changes you would have to update your local copy manually. So the default option is to use the UI assets hosted on opensprinkler server, this way updates are automatically accessible to everyone.June 28, 2015 at 10:33 pm #38798
Regarding the addition of the lcd, it could be stacked above the pi board but the board is faced the wrong way for that. If the pins needed were added to the OSPi board offset from the edge of the RPi board then with long headers it could be easily mounted. A taller case would probably be needed but I would think it would fit into the higher case that has been noted other places (would need the user to cut the holes). I have sketched the stacking if my description isn’t clear. I could also add a board between the RPi and OSPi to bring the header to the side with no changes to the Pi or OSPi but the height increases(top sketch).
I take it the note on hosting the webUI on the RPi is in regard to no network connection. I realize I wouldn’t get automatic time setting/sync so the time would drift a bit and have to be set manually. The battery should handle power outages though. Any other limitations with no network connection?
For some reason the jpg file doesn’t seem to show up when I post.June 29, 2015 at 12:55 am #38803
Regarding pins: please note that all RPi pins are mapped out to the pinout area close to the top of the circuit board. Whichever pin you need to use, you can find it available there.
With no network connection, you will lose features such as weather-based adjustment, remote access, and time sync as you remarked.June 29, 2015 at 6:54 am #38807
Thanks Ray. It looks like the layout matches the RPi if the RPi were flipped over so if I use long enough pins any board that would plug into the RPi would plug right in sitting above the RPi. It’s obvious now – don’t know how I missed that.August 2, 2015 at 5:22 pm #39633
I am still trying to get my head around the software. There seems to be several choices (unified, python interval program, and sprinklers_pi). I haven’t found much to guide a newbie on the choice except for the comments in the manual that you can choose which one when you start up the system. I want to add a LCD/keypad for local control/maintenance people. People have commented that it’s possible and that they have done it but haven’t posted the details/code (that I know of). Am I missing something or these things not detailed very well? I suppose some of this may become more clear once I get a system and start playing with it but I don’t want to spend lots of time fighting with software. Want to make sure it will do what I want before I jump in.
Was just looking at the github link Ray posted. It links to a PIC I2C decoder. Wondering if the code is compatible with this:
which uses a MCP23017 I2C chip.
Can someone confirm this was rolled into the latest unified software? I see mention of the LCD. Is there any keypad support?August 2, 2015 at 10:32 pm #39642
I2C LCD support has not been integrated with the latest firmware yet. The pull request here:
implements the I2C LCD for OSPi/OSBo, and it uses a pretty common I2C LCD that you can easily source on eBay or Amazon. It’s based on PCF8574 I/O expander. It is NOT compatible with MCP23017.
Honestly if LCD and buttons are important for you, you should probably consider the fully assembled OpenSprinkler 2.3. The unified firmware works for both hardware.July 31, 2016 at 6:57 pm #43599
has anyone had any updates on the i2c lcd screen and how to make it work with ospi? I know there is a link that mentions it but no step by step for noobs to actually use it. I have asked for help but it has been months and I have had not one reply.September 6, 2017 at 3:51 pm #47605
Hi guys, I have temporary workaround for this problem until somebody will do the full support. I’ve just finished python script which gets data from OpenSprinkler API and sends to I2C LCD. Both 16×2 and 20×4 I2C LCDs are supported. Script is executed via cron in one minute interval. Details can be found on GitHub: https://github.com/stanoba/ospiLCD.
Is anybody willing to test it?September 7, 2017 at 8:16 am #47613
Looks good! I have a AdaFruit LCD that uses the MCP23017. I can’t test it right away but will give it a try. It appears that I can define the MCP23017 and it should work? The use of the small adapter board with pull ups isn’t clear to me – when is that to be used?
You say “temporary” and I am noticing this idea has been kicking around for over two years. Might be one of those permanent temporary things… 🙂September 7, 2017 at 10:24 am #47615
Yes, all three expanders should work as they are supported by RPLCD library. I have only cheap PCF8574T I2C LCD, so I’m glad that other boards will be tested.
The small adapter should replace dupont cables in the future. I’m planning to rework this ospi enclosure and make holes for few types of LCDs.
PS: Yes you right. Probably this is going to be permanent solution… 🙂
- You must be logged in to reply to this topic.