Making a grilling station: a few Puck.js questions

Hello everyone,

First off - really excited about Espruino boards and their capabilities given extremely low power consumption.

I came up with a simple idea of getting better control of the grilling temperature by using 2 espruinos: one takes the measurements with MAX31855 + thermocouple and advertises temperature; another one collects the temp and shows the stuff using Sharp memory display; there will be a piezo beeping in case temperature gets too high.

So the setup is quite simple, I did some quick and dirty testing with Puck.js I had already and connected both screen and thermocouple amplifier to it (and thermocouple to amplifier to get temp measurements).

Everything works like a charm as you can see from the pic attached. As a next step I ordered MDBT42Q as a second device, which will work with a screen, and Puck is expected to take measurements.

So here are some qqs that I'd appreciate help with

1. The screen shows inverted image currently, what's the way to get black text / white background?
   
2. In advertising mode only (no screen connected) with MAX31855 attached power consumption seemed close to zero = it kept around 100% for a couple days I kept it on. With the screen attached additionally it was draining roughly 0.5-1% per hour, which is not bad, but it can be better I believe. How to do so? Reducing baud rate? Less frequent screen updates? If so, how to manage do it?
   
3. Is there any way to completely switch off the screen with a command, given it is attached to power (I guess no)?
   
4. Is there any way to completely switch off Puck.js with an external switch without removing a battery?
   
   

So far the plan I have is to use for the "screen" device

• MDBT42Q
  
• battery holder
  
• kill switch
  So that let's say after temperature gets low, the device turns off automatically, but I'm still very interested in making both "screen" and "sensor" parts work as long a possible without changing the battery.
  
  

Thanks!

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