# 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. ![Alt](/.gitea/webview0.png "Web view demo") ## 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 # 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 # 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 ```