The user interface of the data logger is an interactive menu. There are some common usage principles: The inverted area on the screen is the current selected menu or item. You can control the selection using the arrow keys.
For the start, a short video which gives you an impression how you navigate in the menus.
Each menu is explained in the following sections.
The main menu shows all possible actions. You can use arrow up and down to navigate this menu. Press enter to select the action.
The info bar at the bottom shows the current date and time, and the current readings from the sensor. A small dot between the humidity and temperature indicates the data logger is in power save mode.
If you select “Start Rec.”, the data logger switches into power save mode and starts recoding data in the selected interval. You can see the current number of records in the line prefixed with “R:”, and the maximum number of records.
To stop recording, press the arrow left key. In power save mode you have to press the key a little bit longer.
If the memory is full, a message appears but the data logger stays in power save mode.
You can view all records using this action. Navigate using the up and down arrow. You can select the step size using the arrow right key between 1, 10 and 100. Press the arrow left key to go back to the main menu.
For this action you need an attached TTL cable and an open serial console. If you select this action, all records are sent as comma separated list to the serial port. By default a connection speed of 9600 baud is used. I planed to implement an action to change the baud value as well, but there was no memory left for this.
Here you can select the recording interval. Move the selection using the up and down arrow and select a new value using the enter key. If you press the left key, you leave this selection without change.
The checkmark shows the current selected interval.
This action is to erase all records from the memory. A countdown is shown starting with 10. Each time you press the enter key, the number goes down. If you reach zero, all data is erased. If you press the left key before you reach zero, nothing is erased.
You can adjust the date and time of the real time clock with this action. You can select the date/time element using arrow up and down and change the values using the left and right arrow. To cancel this action, navigate to the line “Cancel” and press enter. To adjust the real time clock to the shown values, navigate down to the line “Adjust Time” and press enter. The seconds are set to zero.
This action shows the current version number of the software. Press arrow left to return to the main menu.
Interested to build your own version? Read more about the used parts.