# Lcd Functions Overview

### Description

Lcd functions allow scripts to interact with the transmitter display. This access is limited to the 'run' functions of One-Time and Telemetry scripts. Widget scripts on the Horus (X10 and X12S) can make use of the lcd functions as well.

### Notes:

The run function is periodically called when the screen is visible. In OpenTX 2.0 each invocation starts with a blank screen (unless lcd.lock() is used). Under OpenTX 2.1 screen state is always persisted across calls to the run function. **Many scripts originally written for OpenTX 2.0 require a call to lcd.clear() at the beginning of their run function in order to display properly under 2.1 and 2.2.**

Many of the lcd functions accept parameters named *flags* and *patterns*. The names and their meanings are described below.

## Flags Constants

| Name          | Description                                | Version | Notes                                             |
| ------------- | ------------------------------------------ | ------- | ------------------------------------------------- |
| 0             | normal font, default precision for numeric |         |                                                   |
| DBLSIZE       | double size font                           |         |                                                   |
| MIDSIZE       | mid sized font                             |         |                                                   |
| SMLSIZE       | small font                                 |         |                                                   |
| INVERS        | inverted display                           |         |                                                   |
| BLINK         | blinking text                              |         |                                                   |
| XXLSIZE       | jumbo font                                 | 2.0.6   |                                                   |
| LEFT          | left justify                               | 2.0.6   | Default for most functions not related to bitmaps |
| RIGHT         | right justify                              |         |                                                   |
| PREC1         | single decimal place                       |         |                                                   |
| PREC2         | two decimal places                         |         |                                                   |
| GREY\_DEFAULT | grey fill                                  |         |                                                   |
| TIMEHOUR      | dislay hours                               |         | Only for drawTimer                                |

## Patterns Constants

| Name   | Description              |
| ------ | ------------------------ |
| FORCE  | pixels will be black     |
| ERASE  | pixels will be white     |
| DOTTED | lines will appear dotted |

## Screen Constants

| Name   | Description      |
| ------ | ---------------- |
| LCD\_W | width in pixels  |
| LCD\_H | height in pixels |

## Screen Information

| Radio | LCD\_W | LCD\_H | Colours |
| ----- | ------ | ------ | ------- |
| X7    | 128    | 64     | 1 bit   |
| X9D   | 212    | 64     | 4 bit   |
| X9D+  | 212    | 64     | 4 bit   |
| X9E   | 212    | 64     | 4 bit   |
| X10   | 480    | 272    | RGB565  |
| X12S  | 480    | 272    | RGB565  |


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