119 lines
3.4 KiB
Markdown
119 lines
3.4 KiB
Markdown
# TH7
|
|
|
|
### Seven-channel multiple thermocouple reader and logger HAT for the Raspberry Pi.
|
|
|
|
This software supports the following thermocouple types:
|
|
|
|
- B
|
|
- E
|
|
- J
|
|
- K
|
|
- N
|
|
- R
|
|
- S
|
|
- T
|
|
|
|
Features not yet implemented but planned:
|
|
|
|
- More database logging options than SQLite3 and InfluxDB
|
|
- Advanced filtering, incl. user-selectable filtering stages and sample sizes
|
|
- Several logging options at once, one local, one or more remote
|
|
- Configure any setting via API call either via RESTful JSON API or GRPC
|
|
- A terminal user interface ("TUI") that may be used to remotely monitor/access/configure a TH7 (w/ auth)
|
|
- Ability to act in headless mode
|
|
- Request dumps from filter stages for noise study
|
|
- ... and more!
|
|
|
|
###### Note: Most thermocouples that have a coloured and a white lead, usually have the coloured one as the positive.
|
|
|
|
|
|
|
|
## Configuring the TH7
|
|
|
|
This program is controlled with a config file `config.toml` in which the user can configure each thermocouple channel independently, enable a web view, configure database logging, etc.
|
|
The TH7 software uses sane default values where possible.
|
|
|
|
```toml
|
|
# EXAMPLE TH7 CONFIG
|
|
[TH7]
|
|
port = 9090 # port used by the web view
|
|
LED = true # enable the blinking lights on the Raspberry Pi Hat
|
|
debug = false # if true, the software will use a simulated TH7
|
|
nolog = false # debug variable, will simulate a DB
|
|
noweb = false # set to true to disable web view and the REST API
|
|
|
|
# Configure channel 1
|
|
[Channel_1]
|
|
type = 'K' # set type to K-type thermocouple
|
|
gain = 106.8 # gain is used during signal conversion
|
|
offset = -5.6 # offset is added to the final converted value (in °C)
|
|
filter.samples = 50 # samples for the filter function
|
|
filter.type = 0 # integer representing the filter function type
|
|
log = false # do not log this channel to DB (if applicable)
|
|
|
|
# Filter functions:
|
|
# 0: simple alpha-beta filter (default)
|
|
# 1: lag filter: old * 0.90 + new * 0.10
|
|
# 2: lag filter: old * 0.95 + new * 0.05
|
|
# 3: lag filter: old * 0.99 + new * 0.01
|
|
|
|
# Configure channel 2 to read μV
|
|
# this example uses default values for gain, offset and filter.
|
|
[Channel_2]
|
|
type = 'U' # set thermocouple type to 'U' to just read μV
|
|
|
|
# Database
|
|
# Each database type requires its own set of values
|
|
# Below is an example for SQLite3
|
|
[DB]
|
|
type = "sqlite3"
|
|
path = "/home/pi/th7.db" # where to save the database file
|
|
freq = 60 # logging frequency. specified in seconds
|
|
|
|
# InfluxDB example
|
|
[DB]
|
|
type = "influxdb"
|
|
host = "https://influxdb-server.com/"
|
|
bucket = "my-th7-bucket"
|
|
token = "cGFzc3dvcmQxMjMKcGFzc3dvcmQxMjMK"
|
|
```
|
|
|
|
### Using InfluxDB
|
|
|
|
The `host`, `bucket` and `token` fields may be specified in the env variables, rather than in the `config.toml` file. Example:
|
|
|
|
```shell
|
|
export INFLUXDB_HOST="https://influxdb-server.com/"
|
|
export INFLUXDB_BUCKET="my-th7-bucket"
|
|
export INFLUXDB_TOKEN="cGFzc3dvcmQxMjMKcGFzc3dvcmQxMjMK"
|
|
```
|
|
|
|
In this case, the `[DB]` field in `config.toml` can be left empty except for `type = "influxdb"`
|
|
|
|
## Building on a Raspberry Pi
|
|
|
|
This code builds without fuss on Raspberry Pi 4 with go version go1.19.3 linux/arm
|
|
|
|
```shell
|
|
wget https://go.dev/dl/go1.19.3.linux-armv6l.tar.gz
|
|
sudo rm -rf /usr/local/go && sudo tar -C /usr/local -xzf go1.19.3.linux-armv6l.tar.gz
|
|
```
|
|
|
|
edit $HOME/.profile and add the following, if not already there:
|
|
|
|
```shell
|
|
export PATH=$PATH:/usr/local/go/bin
|
|
```
|
|
|
|
source new profile
|
|
|
|
```shell
|
|
. $HOME/.profile
|
|
```
|
|
|
|
then try to build
|
|
|
|
```shell
|
|
make
|
|
```
|