Displays

Supported Displays~

Display Commands~

See commands page for full list of available Display Commands

DisplayMode~

The display driver is able to display predefined setups of text or user defined text. To display text using DisplayText set DisplayMode to 0, or set DisplayMode to 1 for the HT16K33 dot-matrix display.

To use the seven-segment-specific TM1637, TM1638 and MAX7219 or TM1650 Display- commands, set DisplayMode to 0.

DisplayText~

The DisplayText command is used to display text as well as graphics and graphs on LCD, OLED and e-Paper displays (EPD). The command argument is a string that is printed on the display at the current position. The string can be prefixed by embedded control commands enclosed in brackets [].

In order to use the DisplayText command the DisplayMode must be set to 0 (or optional 1 on LCD displays) or other modes must be disabled before compilation with #undef USE_DISPLAY_MODES1TO5.

The DisplayText command is customised for the TM1637, TM1638 and MAX7219 or TM1650 seven-segment display modules. This is documented here and here.

DisplayText Parameters~

In the list below p stands for parameter and may be a number from 1 to n digits. On monochrome graphic displays things are drawn into a local frame buffer and sent to the display either via the d command or automatically at the end of the command.

Co-ordinates are mapped from 0,0 (x,y) at the top left of the logical display, where x is the horizontal axis incrementing right and y is the vertical axes incrementing down. How the logical display is physically displayed (rotated) on screen can be adjusted on some displays using the DisplayRotate command.

Positioning~

lp = sets a character line to print at (on LCD display p = {0…}, on TFT display p = {1…})
cp = sets a character column to print at (on LCD display p = {0…}, on TFT display p = {1…})
xp = sets the x position for consecutive prints
yp = sets the y position for consecutive prints

Text is printed at the last provided position, either l or y for the vertical position, and either x or x for the horizontal position. Neither x nor y are advanced/updated after printing text.

Line Primitives~

hp = draws a horizontal line with length p (x is advanced)
vp = draws a vertical line with length p (y is advanced)
Lp:p = draws a line to destination p:p (x,y are advanced)
kp = draws a circle with radius p
Kp = draws a filled circle with radius p
rp:p = draws a rectangle with p width and p height
Rp:p = draws a filled rectangle with p width and p height
up:p:p = draws a rounded rectangle with p width, p height and p radius v Up:p:p = draws a filled rounded rectangle with p width, p height and p radius

Miscellaneous~

z = clear the display
i = (re)init the display (in e-Paper mode with partial update)
I = (re)init the display (in e-Paper mode with full update)
d = update the display
Dp = switch display drawing options:
bit 0: auto updates => 1 auto draw on each displaytext cmd, 0 display must be updated manually with d
( only valid for bw oled and epaper displays, color displays draw always immediately)
bit 1: character drawing => 0 opaque character drawing, 1 transparent character drawing
o = switch display off
O = switch display on
ap = p (0..3) set rotation angle
t = display Tasmota time in HH:MM
tS = display Tasmota time in HH:MM:SS
T = display Tasmota date in DD.MM.YY
pp = pad text with spaces, positive values align left, negative values align right
sp = set text scaling for all fonts (scaling factor 1...N)
fp = set font (1=12, 2=24,(opt 3=8)) if font==0 the classic GFX font is used, if font==7 RA8876 internal font is used, if font==4 special 7 segment 24 pixel number font is used, a ram based font is selected if font==5
Cp = set foreground color (0,1) for black or white and RGB decimal code for color (see color codes)
Bp = set background color (0,1) for black or white and RGB decimal code for color (see color codes)
Cip = set foreground index color (0..31) for color displays (see index color table below)
Bip = set background index color (0..31) for color displays (see index color table below)
wp = draws an analog watch with radius p (#define USE_AWATCH)
Pfilename: = display an rgb 16-bit color (or jpg on ESP32) image when file system is present, Scripteditor contains a converter to convert jpg to special RGB16 pictures See ScriptEditor
Pfilename:C:ys:ys displays a centered picture in frame xs, ys. if C > 0 the picture gets a frame in this index color
Ffilename: = load RAM font file when file system is present. the font is selected with font Nr. 5, these fonts are special binary versions of GFX fonts of any type. they end with .fnt. an initial collection is found in Folder BinFonts
SXfilename: = load display descriptor for multiple display support (X = 1..3) for up to 3 displays.
SX: = switch to display number (X = 1..3).
dcI:V = define index color entry Index 19-31, V 16 bit color value (index 0-18 is fixed)

Touch Buttons and Sliders~

Requires #define USE_TOUCH_BUTTONS

Draw up to 16 GFX buttons to switch real Tasmota devices such as relays or draw Sliders to dimm e.g. a lamp

• Button number + 256 - a virtual touch toggle button is created (MQTT => TBT)
• Button number + 512 - a virtual touch push button is created (MQTT => PBT)

b#:xp:yp:xa:ys:oc:fc:tc:ts:text:
Parameters are separated by colons.

• b# where # = define a button number 0-15
• xp = x position
• yp = y position
• xa = x size
• ys = y size
• oc = outline index color
• fc = fill index color
• tc = text index color
• ts = text size on buttons
• text: = button text (must end with a colon :) (max 9 chars)

Picture Buttons~

To create picture touch buttons (jpg on ESP32 only) requires #define JPEG_PICTS and #define USE_UFILESYS.

Upload pictures to the file system with a ".jpg" extension, then give the path to the picture as button text omitting the .jpg extension.

The size of the picture is not scaled and the dimensions of the button must fit the picture size. Clicked buttons will invert the colors of the picture.

You may specify a picture for selected and unselected button state. Picture filename ending with '1' is used for unselected state and ending '2' is for selected state.

Sliders~

• bs# where # = is slider number 0..15
• xp = x position
• yp = y position
• xa = x size
• ys = y size
• ne = number of elements
• bc = background color
• fc = frame color
• bc = bar color

Set the state of a button or slider with:

• b#sX where # = is slider or button number 0..15
• X = 0 or 1 for buttons, 0..100 for sliders

Disbale button or slider with:

• bd# disbale where # = is slider or button number 0..15
• be# enable where # = is slider or button number 0..15

Display JSON variables~

Requires #define USE_DT_VARS

Display variables that are exposed in JSON MQTT strings e.g. in TelePeriod messages.

The values are updated every second.

dv#:xp:yp:gc:fc:fo:ts:tl:dp:ut:JSON:ut:
Parameters are separated by colons.

• dv# where # = defines a variable number 0-7 (may be expanded by #define MAX_DT_VARS N)
• xp = x position
• yp = y position
• gc = text background color (index color)
• fc = text foreground color (index color)
• fo = text font
• ts = text size (negative value denotes transparent text)
• tl = text field length (if negative align right)
• dp = decimal precision (if < 0 denotes a string)
• ut = update time in seconds (1...N)
• jt = JSON VARIABLE NAME (uppercase) if you specify a string in brackets here it is treated as displaytext cmd
• ut = unit string (max 5 chars and must end with a colon :)

example:

;ILI9341 320x240 portrait mode
[x0y0P/corona.rgb:]
[dc19:31000]
[x60y30f2Ci3D2]Tasmota
; display text cmd displays time with seconds
[dv0:50:70:19:3:2:1:11:1:1:[tS]::]
; display text cmd displays analog watch
[dv1:120:250:19:2:2:1:11:1:5:[w40]::]
; displays Wifi SSID JSON
[dv2:10:10:0:3:1:-1:10:-1:1:WIFI#SSID::]
[x10y150f1s1Ci3Bi19]Counter:
; displays a sensor JSON variable (here counter1)
[dv3:80:150:0:7:1:1:11:0:1:COUNTER#C1:cnt:]
[x10y300f1s1Ci3Bi19]memory free:
; displays pre memory space JSON (heap)
[dv4:100:300:0:7:1:1:-7:-1:1:HEAP:kb:]

Line chart~

(#define USE_GRAPH and #define NUM_GRAPHS 4 - maximum of 16)

Up to 4 line charts may be defined.

Ticks may be defined by adding tick numbers to the n parameter.

Gn:xp:yp:xs:ys:t:fmax:fmin defines a line chart:
Parameters are separated by colons.

• n = number up to 4 charts (0..3) + optional ticks
• xp = x position
• yp = y position
• xs = x size (if xs<0) graph is not reinitialized on second call (e.g., restart of scripter)
• ys = y size
• t = time in minutes for total chart
• ymin = float chart minimum y
• ymax = float chart maximum y
• icol = line color index (only for color graphs)

gn:v adds a value to the chart buffer:

• n = number up to 4 charts (0..3)
• v = float value to add

Gdn:m sets graph n draw mode 0 = off, 1 = on. When on, redraw graph

• Gsn:path: = save graph n to path (if optional file system is present)
• Grn:path: = restore graph n from path (if optional file system is present)

Batch files~

When a file system is present you may define displaytext batch files. If a file named "display.bat" is present in the file system this batch file is executed. The file may contain any number of diplaytext cmds, one at a line. You may have comment lines beginning with a ;

; clr screen
[z]
; draw full screen picture
[x0y0P/corona.rgb:]
; define index color
[dc19:31000]
; draw transparent text with new index color over picture
[x60y30f2Ci19D2]Tasmota

Color Codes~

While computers and web design are generally using a 24-bit RGB888 color code built from a byte-triplet such as (255, 136, 56) or #FF8038, small color panels often use a more compact code 16-bit RGB565 color code. This means that the R, G and B coefficient are coded on less number of bits:

• Red on 5 bits = 0..31
• Green on 6 bits = 0..63
• Blue on 5 bits = 0..31

For Cp and Bp, p is calculated as p = 2048 * Red + 64 * Green + Blue

Common colors table:

Color Indices~

Selected with Ci and Bi in the ILI9488, SSD1351, RA8876 and ST7789 color panels

You may expand the index color table up from index 19 to 31. the cmd [dcI:V] defines the index color with index I (19-31) to the 16 bit color value V

Note on e-Paper Displays~

E-Paper displays have 2 operating modes: full update and partial update. While full update delivers a clean and sharp picture, it has the disadvantage of taking several seconds for the screen update and shows severe flickering during update. Partial update is quite fast (300 ms) with no flickering but there is the possibility that erased content is still slightly visible. It is therefore useful to perform a full update in regular intervals (e.g., each hour) to fully refresh the display.

Compilation directives: #define USE_SPI, #define USE_DISPLAY, #define USE_DISPLAY_EPAPER29, or #define USE_DISPLAY_EPAPER42

Remark: the 4.2 e-Paper display requires about 15k of RAM. Therefore it only works with Core 2.42 and above.

OLED Lifetime~

The typical specifications for the lifetime of an OLED when permanently on is about 10000 hours (416 days). Dimming to 50% expands the lifetime to about 25000 hours.

Burn-in~

The data sheets of the TFT and OLED displays mention burn-in effects when a static display is shown for extended periods of time. You may want to consider turning on the display on demand only.

Fonts~

The EPD font contains 95 characters starting from code 32, while the classic GFX font contains 256 characters ranging from 0 to 255. Custom characters above 127 can be displayed. To display these characters, you must specify an escape sequence (standard octal escapes do not work). The ~character followed by a hex byte can define any character code.

GFXFont:

EPDFont:

Hardware Connections~

I²C displays are connected in the usual manner and defined via the GPIO component selection.

The I²C address must be specified using DisplayAddress XX, e.g., 60. The model must be specified with DisplayModel, e.g., 2 for SSD1306. In versions with Universal Display Driver the DisplayModel is always 17. To permanently turn the display on set DisplayDimmer 100. Display rotation can be permanently set using DisplayRotate X (x = 0..3). On SPI the CS and DC pins when needed must use the pin definition with Display_ID + CS e.g. ST7789_CS

E-Paper displays are connected via software 3-wire SPI (CS, SCLK, MOSI). DC should be connected to GND , Reset to 3.3 V and busy may be left unconnected. The jumper on the circuit board of the display must be set to 3-wire SPI.

The ILI9488 is connected via hardware 3-wire SPI (SPI_MOSI=GPIO13, SPI_SCLK=GPIO14, CS=GPIO15) and must also be connected to the backlight pin The SSD1351 may be connected via hardware 3-wire SPI or 4-wire SPI with support for dimmer. The ILI9341 is connected via hardware 4-wire SPI, Backlight and OLEDRESET (dimmer supported on ESP32) Wiring

The RA8876 is connected via standard hardware 4-wire SPI (SPI_MOSI=GPIO13, SPI_SCLK=GPIO14, RA_8876_CS=GPIO15, SSPI_MISO=GPIO12). No backlight pin is needed, dimmer supported, on ESP32 gpio pins may be freeley defined (below gpio 33).

The ST7789 is connected via 4 Wire software SPI ((ST7789_CS), SSPI_SCLK, SSPI_MOSI, ST7789_DC, OLEDRESET, Backlight )

Rule Examples~

Print Text at size 1 on line 1, column 1:
DisplayText [s1l1c1]Hello how are you?

Draw a rectangle and draw text inside with size 2 and 7 chars padded with spaces:
DisplayText [x85y95h130v30h-130v-30s2p7x90y100]37.25 C

Refresh screen:
DisplayText [z]

Draw rectangle from x,y with width and height:
DisplayText [x50y50r200:100]

Display Local Sensors~

(line breaks and indentation added to the rules for readability)

Use Tasmota rules to display sensor values, time, and a separation line. Refresh the display every 60 minutes:

rule1 on tele-SHT3X-0x44#Temperature do DisplayText [f1p7x0y5]%value% C endon
      on tele-SHT3X-0x44#Humidity do DisplayText [f1p10x70y5]%value% %[x0y20h296x250y5t] endon
      on tele-BMP280#Pressure do DisplayText [f1p10x140y5]%value% hPa endon
      on Time#Minute|60 do DisplayText [Tt] endon

Show 4 analog channels:

rule1 on tele-ADS1115#A0 do DisplayText [s1p21c1l01]Analog1: %value% adc endon
      on tele-ADS1115#A1 do DisplayText [s1p21c1l3]Analog2: %value% adc endon
      on tele-ADS1115#A2 do DisplayText [s1p21c1l5]Analog3: %value% adc endon
      on tele-ADS1115#A3 do DisplayText [s1p21c1l7]Analog4: %value% adc endon

Show BME280 + SGP30:

rule1 on tele-BME280#Temperature do DisplayText [s1p21x0y0]Temp: %value% C endon
      on tele-BME280#Humidity do DisplayText [s1p21x0y10]Hum : %value% %% endon
      on tele-BME280#Pressure do DisplayText [s1p21x0y20]Prss: %value% hPa endon
      on tele-SGP30#TVOC do DisplayText [s1p21x0y30]TVOC: %value% ppb endon
      on tele-SGP30#eCO2 do DisplayText [s1p21x0y40]eCO2: %value% ppm [s1p0x0y50]Time: [x35y50t] endon

WaveShare Display Drivers~

Waveshare has two kinds of display controllers: with partial update and without partial update. The 2.9 inch driver is for partial update and should also support other Waveshare partial update models with modified WIDTH and HEIGHT parameters. The 4.2 inch driver is a full update display.

epaper displays should be connected via software SPI. most of them require a reset and a busy line. connect the busy line to SSPI_MISO.

The drivers are subclasses of the Adafruit GFX library. The class hierarchy is LOWLEVEL :: Paint :: Renderer :: GFX, where:

• GFX: unmodified Adafruit library
• Renderer: the interface for Tasmota
• Paint: the modified pixel driver for e-paper
• there are several virtual functions that can be subclassed down to LOWLEVEL

The display dispatcher only does the class initialization call. All other calls go to the Renderer class.

In black and white displays, a local RAM buffer must be allocated before calling the driver. This must be set to zero on character or TFT color displays.

The EPD fonts use about 9k space, which can be selected at compile time using #ifdef directives.

• SSD1306 - 1.15k
• EPD42 - 2.57k
• EPD29 - 2.1k
• Display and Render class - ~12k

Universal Display Driver~

Documentation for Universal Display Driver was moved to a specific page

Universal Touch Driver~

Documentation for Universal Touch Driver was moved to a specific page

Compiling~

There are also many variants of each display available and not all variants may be supported.