> For the complete documentation index, see [llms.txt](https://docs.lorric.com/qr/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.lorric.com/qr/fu-tx310-ultrasonic-flowmeter-manual-en-v2/1-product-introduction/1.7-user-interface/1.7.2-buttons.md).

# 1.7.2 Buttons

There are four buttons at the bottom of the screen; their corresponding functions are shown on the lower edge of the screen: 

From left to right order of view: Button one: 

● Switch the interface. 

● Back to the previous level (the multi-level interface).

Button two: 

● When < ​is displayed: Returns to the previous option or interface; moves between choices after entering the interface.&#x20;

● When +​ is displayed: Edit the number.

![](/files/-LrDX-zwf_dA1KlRABgF)

![](/files/-LrDX3dS1dnyO3AlcslN)

Button three:&#x20;

● Select the next menu or interface.&#x20;

● When editing numbers, jump to the next digit.

Button four:&#x20;

● When ENT​ is displayed: Press Enter to enter the selected menu.&#x20;

● When SET​ is displayed: Press to set the content entered.&#x20;

● When PAUSE​ is displayed: Press to pause measurement, Red light will flash.&#x20;

● When START​ is displayed: Press to continue measurement and release PAUSE​ status.

![](/files/-LrDZ5rQuNqYIVaZ4R2z)


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