STM32 Config

Emoncms configuration module for raspberry pi based installations of emoncms with an stm32 based emonBase

[screenshot of Module page displaying STM32 inputs]

download

clone this repo:

git clone git@github.com:emoncms/stm32config.git

install

create a link to the module directory (stm32config-module) in the emoncms Modules directory.

sudo ln -s [/path/to/this/repo/]stm32config-module /var/www/emoncms/Modules/stm32config

run

click the STM32Config link in the emoncms sidebar to see the list. eg: http://localhost/emoncms/stm32config/

Module Parts

MQTT

The STM32Config Module will subscribe to a specific MQTT "Request topic" that contains the STM32 chip commands.

Once a command is received via MQTT the module will forward the command via serial connection to the STM32 chip.

Using MQTT with this module has another advantage in that EmonCMS is already set up to take input data via MQTT.

This makes is very easy to forward any STM32 serial data to EmonCMS

Serial Data

The hardware serial connection is between UART1 on the STM32 and the UART port on the rPi.

The serial data is divided into Codes, Get/Set Flag, Keys, Properties, and Values.

Code. This is a way to help organise the set of commands. The code is sent with the commands and is received with the response, acting as a parity check.
Get/Set Flag. This divides a command into either a request for data (GET) or setting change (SET), such as setting the RTC time.
Keys. The STM32 chip has input/output ports and devices, KEYS represent Current Transformers, MBUS connections, Input/Outputs and any other sensors.
Properties. The specific setting of a device. For example, a CT can have Set the burden resistor value, or which VT it's assigned to. Or a VT can have Get the state, i.e. whether or not it is connected.
Value. The value of the data, could be anything, boolean, integer, float or JSON string for example.

All the KEYS and PROPERTIES have Short Names, listed below.

Here are some examples of the serial command sent to the chip (using action and key short names): eg:

GET -> CT1 -> Real Power G:CT1:RP
SET -> VT1 -> Phase = 2.52 G:CT1:RP:2.52

As the python script receives serial data, the feed is processed and publish the result to a Response topic that matches the original request id.

The original HTTP request to EmonCMS will subscribe to the Response topic and return the results to the user.

Returned Data Structures

The different parts of this system return different data structures:

User Interface

The module can be interacted with via a EmonCMS page.

Most of the interactions will be done using javascript and displayed to the user using vue.js templates.

The vue.js template requires JSON data given to it with the following success,message,data properties :-

{
    "success": true,
    "message": "Value received",
    "data": [
        {
            "property" : "voltage",
            "key" : "VT1",
            "value" : 244.12
        }
    ]
}

Short Names:

To keep the serial comms efficient we have used "Short Names" to describe elements in the system. Listed HERE.

To interpret a serial instruction refer to the example table below:

Short Name	Instruction	Description
G	GET	Get a Key's value
S	SET	Set a Key's value
L	LIST	List all Keys
SAMP	SAMPLE	Get sequence of Key's values
DUMP	DUMP	Get the standard output
BAK	BACKUP	Get the config settings

Keys

Within the context of this module the name KEYS is given to refer to the STM32 Inputs, Outputs or any other Devices.

Key	TYPE
CT1-CT9	INPUT
VT1-VT5	INPUT
SYS	SYSTEM
LED1	OUTPUT
MBUS	INPUT
TEMP	INPUT
PULSE	INPUT
IRDA	INPUT

Properties

Different KEY types will have different properties. Each property is given a Short Name. Short Names can conflict across KEY types.

eg. The Short Name "V" represents differnet properties by the SYS and VT1 keys.

Short Name	Property	Example Key
V	Voltage	VT1
RP	RealPower	CT1
C	Current	CT1
PF	PowerFactor	CT1
ON	On	LED1
V	Version	SYS

danbates2/stm32config