Will the Fin work for me?

balenaFin
1

I want to learn IoT systems by installing a SoC in my off-grid trailer and monitoring system voltages (a few), a few temperatures, and some mechanical states (switches on hatches). I will eventually want to use PWM to control a motor or two.

  1. Is a balenaFin going to work for my application, in general?
  2. Will the Phoenix “ring” exposed terminals give me the correct access to achieve what I want in a robust manner? (GPIO/ADC/PWM)

I did read the datasheet, but I don’t yet have the knowledge to understand what I’m looking at.

Thanks for your input and comments,

A.

2

Hey Adam,

Yes, balenaFin sounds like an ideal candidate for your use-case. In essence, you would want to use the co-processor for real-time signals, such as PWM and for analog input. To monitor system voltages, ideally you would want to use some intermediary board, as the co-processor supports up to 3.8 voltage and the GPIO support up to 5v.

Thanks for reaching out and we are looking forward to hearing more about your use-case :slight_smile:

1 Like
5

Thanks for the support!

A few more questions:

  1. Is the ADC and GPIO accessible from the main CPU directly? I’m hoping to leave do-processor programming to a later stage of development.
  2. For convenient 12v vehicle power, should I get a 2-position Phoenix plug and use that instead of the barrel connector?

And indeed, I need to learn about what’s required for accurate voltage measurement in the vehicle power range of 0-18v or so. Maybe I can find something off-the-shelf that has a few inputs and communicates over a bus?

Thanks again,

A.

7

For convenient 12v vehicle power, should I get a 2-position Phoenix plug and use that instead of the barrel connector?

Yes, that makes sense.

Is the ADC and GPIO accessible from the main CPU directly?

I think that we have used Firmata in the past which should do what you want.

9

You are talking about:

Meaning that I would flash this firmware to the co-processor, then use that protocol to talk to it from the main CPU. Seems reasonable. Thanks.

10

That’s the one :+1:

12

I received my fin with the nice Phoenix ring.

The connector pin map:

1272×1362 148 KB

From this I gather that I have access to an SPI bus, an I2C bus, and a PWM output directly from the core CPU module, but no digital I/O or ADC.

I see PD14, PA2, PA3, and PF6 from the co-processor?

The co-processor data sheet:

So I can use those 4 pins as either GPIO or ADC, at runtime? I’m clueless in this area.

Lastly, I need a serial interface (to put my fridge on the 'Net!!!), where do I get that?

Thanks for your input,

A.