Raspberry Pi is famous as hardware for web programmers. It works as a Linux PC, so I'm happy that it's relatively easy to use for people who have even touched Linux.

So, when I enthusiastically connected, "Now, it's a hardware prototype with Raspberry Pi!" .. .. "I can't connect" "What is a circuit diagram !?" "I can't solder ..." You need a lot of different knowledge to make a prototype of hardware.

Even if you don't have knowledge of such hardware, even if you have trouble building a farm, There are tools that can be used from trial production to small lot mass production. This is mille-feuille.

mille-feuille has "automatic wiring function" and "automatic circuit diagram generation function".

Simply put

Automatic wiring function: No need to solder. Just stack Circuit diagram automatic generation function: Fully automatic and simple configuration (Each has the advantage that you don't have to write a hardware farm.)

The point is that you don't have to do anything related to hardware.

Programmers can run it in PHP or Python. When displaying in a graph, it is Javascript. Of course, for normal firmware, all you have to do is hit the library.

This time, based on the Raspberry Pi, which has a cheap CPU board and can be used for small lots of business, I will try using mille-feuille to make a hardware prototype for IoT and M2M.

1, What is mille-feuille?

mille-feuille is a support tool that can automatically recognize and design the hardware to be attached to Raspberry Pi 2, B +, A +. (Connect the pie crust of sweets so that they overlap)

It has two main functions.

a, automatic wiring function

Usually, you make a prototype by manually wiring from the Raspberry Pi to the device. It is a function that automatically "recognizes which device is connected", "automatically connects" the wiring, and "just hits the library without worrying about the terminal number". Since it will be in the same state as when wiring normally, it is a feature that the existing firmware library can be replaced.

b, Automatic circuit diagram generation function

A circuit diagram is required for small lot mass production. It is a function that generates the circuit diagram. This will generate a simple circuit diagram that does not have the above automatic wiring function and looks like a prototype by wiring by hand. Since the firmware related to wiring is also automatically generated, it can be used in the same Web program from trial production to small lot mass production.

2, How to develop with mille-feuille

Roughly, it is made in 4 steps of "assembling", "testing", "automatically generating a circuit diagram", and "making a board".

a, assemble

To assemble, just stack and connect each one. You don't have to think about soldering or complicated wiring. The digital switch inside mille-feuille recognizes the type of wiring and connects it by the instruction from the Python library to be put in Raspberry Pi.

b, test

The program mainly hits the Python hardware library of mille-feuille to run it. You can use any language by hitting the Python hardware library. This time, I prepared PHP and Python samples.

You can easily draw graphs using Google chart.

PHP samples are easy to write. Below is a sample of analog signal acquisition.

`AnalogRead.php`


include ("milpython/mil_analog.php");
$dataCh0 = readAD(0);
$dataCh1 = readAD(1);

Use the Python sample when you want to achieve smoother movement than PHP.

`AnalogRead.py`


#!/usr/bin/python
from mil import mil
from mil import milMod
from mil import AD2ch

mil.init()
modA = milMod.milMod(AD2ch.getAddr(),AD2ch.getIOs())

modA.connect()
dataCh0 = AD2ch.analogRead(0)
dataCh1 = AD2ch.analogRead(1)
modA.disconnect()

c, Automatically generate schematic

To automatically generate a schematic, first collect information about which device is connected to mille-feuille using an application made for the Raspberry Pi. Upload that information to the server for circuit generation, and download the schematic script and the wiring setting file that matches it. When you import the schematic script into free software called Eagle CAD (a license is required for commercial use), the schematic is automatically generated.

d, make a board

Finally, make a board from the completed circuit diagram. There are several ways to make a board from a schematic. Please consider the time and cost when making a selection.

This time I made it based on Raspberry Pi, but it can be attached to mbed etc. mechanically. If the number of compatible models increases, the range of development will expand.

mille-feuille is campaigning on indiegogo. Please share if you like ☆ https://www.indiegogo.com/projects/mille-feuille-automatic-schematic-creation-tool/

[PYTHON] Hardware for web programmers mille-feuille Support tool for Raspberry Pi