The S1 Cafe - Helping Your Espresso Dreams Become Reality

Saw a couple of posts here about hacking the S1 with a non-standard timer, e.g,

http://www.s1cafe.com/viewtopic.php?f=3 ... all#p21953

I decided that it wouldn't be too hard to do this with a Raspberry Pi and a bit of soldier and wires. After a couple of weeks of research and getting my hands dirty, I finally got it all together. I wanted to be able to tell if the machine was on or off, and whether the steam boiler was on or off. A future mod might involve seeing the current temperature, but that might be overboard...

Here are the pics:

http://imgur.com/a/JUAjG

The web site pic:


Cheers!
p.s. Just found another RasPi build here, too:
viewtopic.php?f=34&t=1911&p=22865&hilit ... man#p22865

Congratulations. This is the best one yet!

Thanks! Once I figured out how to open up the controller (thanks to MonkeyK's post I mentioned above), it was a matter of some judicious use of a multimeter and figuring out how to control the buttons. I ended up using an optoisolator that kept the machine's electronics separate from the Raspberry Pi's electronics, so it is relatively safe. The one problem is that I didn't correctly do the math for a resistance for connecting to the ON LED, so it is a bit dimmer than normal. But, seeing as I'm not a fan of the bright flashing green light, this is actually a bit of a bonus! :)

Awesome. Any chance of you wanting to post detailed instructions. I can likely do this, but detailed instructions are always easier to work from than a picture.

Holy cow!
I had been tinkering with just hooking up to turning it on and off. But this i amazing.
Is there any chance you would share schematics and other findings?

Here's the updated information from tofergregg, all credits go to him:

Arduino platform and the code for that is here:

https://github.com/tofergregg/EspressoWemos

The original Raspberry Pi code is here:

https://github.com/tofergregg/EspressoPi

Here's where you can order the bare board:

https://oshpark.com/shared_projects/TAsYDcsG

It appears that he used the WEMOS D1 mini and the Minivialdi shield is built on that. He also added a SD card shield found here:

https://www.amazon.com/ACROBOTIC-ESP826 ... s=wemos+sd

I'll be working on my own mod and will post updated information, including Digikey parts list for folks that venture to build the mod.
If you are familiar with Arduino, that is the way to go. I downloaded the ExpressWemos files, but I needed to add some additional files in Arduino to be able to have the program compile.

I'm undertaking this same project now. I looked at tofergregg's stuff, but I decided to go with a pi zero. They're small, cheap, have built-in wifi, and support for a full web stack.

I now have it rigged together to just power the machine on at fixed times, but I'm going to get some boards spun and a full app built around it in the near future. I'll post details as I get them

I tried building the board but I could not get it to work, loading from the SD card was really slow. I changed my approach and used the ESP8266 with the shield relay and used the Blynk app to turn the espresso on. The only problem is that the Blynk app for IOS does not have the eventor widget, only android phones. The Arduino programming is minimal. I can turn the espresso on in the morning and can turn it on and off from anywhere outside my house. I still need to figure out a shield to read the on/off led to determine the espresso status.

Here is the I/O board I made for my Pi that let's me see the state of the boiler on power leds and remotely hit the boiler and power buttons
I currently have it set up so that I can access and control the current machine state over an http api. It alsostores a summary of each power on cycle in firebase.

which optoisolators did you use?
Would you mind sharing your raspberry pi zero code?

I used PC817 isolators: https://www.farnell.com/datasheets/73758.pdf

Here is the code
https://goo.gl/iW7r7f

Here are the boards I used: https://oshpark.com/shared_projects/xM55dRE8
The oshpark ones needed a few mods to work correctly. The schematic should be updated with the latest version.

Are the mods needed to the layout or the resistor values?

They're to the layout. I had some extra parts on there to monitor the shot buttons, but I decided not to use them. There were also some routing errors and I found out that I needed a cap on the one side of the isolator, before that I was getting some erratic readings. I do have a new board done that should have all the fixes, but I haven't ordered any yet.

Thank you for the clarification. I’ll wait for the updated layout and order a couple of boards.

Here is the updated board.
https://oshpark.com/shared_projects/dyIzPMhS

I doubt I'll order one for a while as this one is already working. But I can help debug if you get one.

I'm loving this solution and can't wait to start. But can anyone tell me what sort of capacitors C1 and C2 are? (as marked on the circuit diagram posted on 22 Nov 2018 by s1guy?)