Display-o-Tron HAT¶

At A Glance¶

LCD¶

lcd.clear()

Clear the display and reset the cursor.

lcd.create_animation(anim_pos, anim_map, frame_rate)

Create an animation in a given custom character slot

Each definition should be a list of 8 bytes describing the custom character for that frame,

Parameters:	anim_pos – Character slot from 0 to 7 to store animation anim_map – A list of custom character definitions frame_rate – Speed of animation in frames-per-second

lcd.create_char(char_pos, char_map)

Create a character in the LCD memory

The st7036 has 8 slots for custom characters.

A char is defined as a list of 8 integers with the upper 5 bits setting the state of each row of pixels.

Note: These slots are also used for animations!

Parameters:	char_pos – Char slot to use (0-7) char_map – List of 8 integers containing bitmap

lcd.set_contrast(contrast)

Set the display contrast.

Raises TypeError if contrast is not an int Raises ValueError if contrast is not in the range 0..0x3F

Parameters:	contrast – contrast value

lcd.set_cursor_offset(offset)

Set the cursor position in DRAM

Calculates the cursor offset based on a row and column offset.

Raises ValueError if row and column are not within defined screen size

Parameters:	column – column to move the cursor to row – row to move the cursor to

lcd.set_cursor_position(column, row)

Sets the cursor position in DRAM based on a row and column offset.

Args:

column (int): column to move the cursor to row (int): row to move the cursor to

Raises:

ValueError: if row and column are not within defined screen size

lcd.set_display_mode(enable=True, cursor=False, blink=False)

Set the cursor position in DRAM

Parameters:	offset – DRAM offset to place cursor

lcd.update_animations()

Update animations onto the LCD

Uses wall time to figure out which frame is current for each animation, and then updates the animations character slot to the contents of that frame.

Only one frame, the current one, is ever stored on the LCD.

lcd.write(value)

Write a string to the current cursor position.

Parameters:	value – The string to write

Backlight¶

backlight.hue(hue)

Set the backlight LEDs to supplied hue

Parameters:	hue – hue value between 0.0 and 1.0

backlight.hue_to_rgb(hue)

Convert a hue to RGB brightness values

Parameters:	hue – hue value between 0.0 and 1.0

backlight.left_hue(hue)

Set the left backlight to supplied hue

Parameters:	hue – hue value between 0.0 and 1.0

backlight.left_rgb(r, g, b)

Set the left backlight to supplied r, g, b colour

Parameters:	r – red value between 0 and 255 g – green value between 0 and 255 b – blue value between 0 and 255

backlight.mid_hue(hue)

Set the middle backlight to supplied hue

Parameters:	hue – hue value between 0.0 and 1.0

backlight.mid_rgb(r, g, b)

Set the middle backlight to supplied r, g, b colour

Parameters:	r – red value between 0 and 255 g – green value between 0 and 255 b – blue value between 0 and 255

backlight.off()

Turn off the backlight.

backlight.rgb(r, g, b)

Set all backlights to supplied r, g, b colour

Parameters:	r – red value between 0 and 255 g – green value between 0 and 255 b – blue value between 0 and 255

backlight.right_hue(hue)

Set the right backlight to supplied hue

Parameters:	hue – hue value between 0.0 and 1.0

backlight.right_rgb(r, g, b)

Set the right backlight to supplied r, g, b colour

Parameters:	r – red value between 0 and 255 g – green value between 0 and 255 b – blue value between 0 and 255

backlight.set(index, value)

Set a specific backlight LED to a value

Parameters:	(int) (value) – index of the LED from 0 to 18 (int) – brightness value from 0 to 255

backlight.set_bar(index, value)

Does nothing.

Implemented for library compatibility with Dot3k backlight.

backlight.set_graph(percentage)

Light a number of bargraph LEDs depending upon value

Parameters:	hue – hue value between 0.0 and 1.0

backlight.single_rgb(led, r, g, b, auto_update=True)

A single backlight LED to the supplied r, g, b colour

The auto_update parameter will trigger a write to the LEDs after the r, g, b colour has been set. Omit it and manually call update() to batch multiple LED changes into one update.

Parameters:	r – red value between 0 and 255 g – green value between 0 and 255 b – blue value between 0 and 255 auto_update – autmatically update the LEDs

backlight.sweep(hue, sweep_range=0.0833)

Set the backlight LEDs to a gradient centered on supplied hue

Supplying zero to range would be the same as hue()

Parameters:	hue – hue value between 0.0 and 1.0 range – range value to deviate the left and right hue

backlight.update()

Update backlight with changes to the LED buffer

backlight.use_rbg()

Does nothing.

Implemented for library compatibility with Dot3k backlight.

Touch¶

touch.bind_defaults(menu)

Bind the default controls to a menu instance

This should be used in conjunction with a menu class instance to bind touch inputs to the default controls.

touch.enable_repeat(enable)

Enable touch hold repeat

If enable is true, repeat will be enabled. This will trigger new touch events at the set repeat_rate when a touch input is held.

Parameters:	enable – enable/disable repeat: True/False

touch.high_sensitivity()

Switch to high sensitivity mode

This predetermined high sensitivity mode is for using touch through 3mm perspex or similar materials.

touch.on(buttons, bounce=-1)

Handle a press of one or more buttons

Decorator. Use with @captouch.on(UP)

Parameters:	buttons – List, or single instance of cap touch button constant bounce – Maintained for compatibility with Dot3k joystick, unused

touch.set_repeat_rate(rate)

Set hold repeat rate

Repeat rate values are clamped to the nearest 35ms, values from 35 to 560 are valid.

Parameters:	rate – time in ms from 35 to 560