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tannewttannewt
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Add a bit more to the docs
1 parent 58a2009 commit dc024cf

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‎shared-bindings/displayio/Display.c‎

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//|
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//| .. warning:: This will be changed before 4.0.0. Consider it very experimental.
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//|
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//| .. class:: Display(display_bus, *, width, height, colstart=0, rowstart=0, color_depth=16,
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//| set_column_command=0x2a set_row_command=0x2b, write_ram_command=0x2c)
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//| .. class:: Display(display_bus, init_sequence, *, width, height, colstart=0, rowstart=0, color_depth=16, set_column_command=0x2a, set_row_command=0x2b, write_ram_command=0x2c)
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//|
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//| Create a Display object.
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//| Create a Display object on the given display bus (`displayio.FourWire` or `displayio.ParallelBus`).
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//|
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//| The ``init_sequence`` is bitbacked to minimize the ram impact. Every command begins with a
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//| command byte followed by a byte to determine the parameter count and if a delay is need after.
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//| When the top bit of the second byte is 1, the next byte will be the delay time in milliseconds.
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//| The remaining 7 bits are the parameter count excluding any delay byte. The third through final
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//| bytes are the remaining command parameters. The next byte will begin a new command definition.
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//| Here is a portion of ILI9341 init code:
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//|
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//| .. code-block:: python
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//|
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//| init_sequence = (b"\xe1\x0f\x00\x0E\x14\x03\x11\x07\x31\xC1\x48\x08\x0F\x0C\x31\x36\x0F" # Set Gamma
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//| b"\x11\x80\x78"# Exit Sleep then delay 0x78 (120ms)
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//| b"\x29\x80\x78"# Display on then delay 0x78 (120ms)
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//| )
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//| display = displayio.Display(display_bus, init_sequence, width=320, height=240)
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//|
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//| The first command is 0xe1 with 15 (0xf) parameters following. The second and third are 0x11 and
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//| 0x29 respectively with delays (0x80) of 120ms (0x78) and no parameters. Multiple byte literals
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//| (b"") are merged together on load. The parens are needed to allow byte literals on subsequent
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//| lines.
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//|
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//| :param displayio.FourWire or displayio.ParallelBus display_bus: The bus that the display is connected to
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//| :param buffer init_sequence: Byte-packed initialization sequence.
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//| :param int width: Width in pixels
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//| :param int height: Height in pixels
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//| :param int colstart: The index if the first visible column
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//| :param int rowstart: The index if the first visible row
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//| :param int color_depth: The number of bits of color per pixel transmitted. (Some displays
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//| support 18 bit but 16 is easier to transmit. The last bit is extrapolated.)
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//| :param int set_column_command: Command used to set the start and end columns to update
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//| :param int set_row_command: Command used so set the start and end rows to update
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//| :param int write_ram_command: Command used to write pixels values into the update region
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//|
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STATIC mp_obj_t displayio_display_make_new(const mp_obj_type_t *type, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
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enum { ARG_display_bus, ARG_init_sequence, ARG_width, ARG_height, ARG_colstart, ARG_rowstart, ARG_color_depth, ARG_set_column_command, ARG_set_row_command, ARG_write_ram_command };

‎shared-bindings/displayio/FourWire.c‎

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@@ -52,6 +52,11 @@
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//|
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//| Create a FourWire object associated with the given pins.
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//|
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//| :param busio.SPI spi_bus: The SPI bus that make up the clock and data lines
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//| :param microcontroller.Pin command: Data or command pin
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//| :param microcontroller.Pin chip_select: Chip select pin
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//| :param microcontroller.Pin reset: Reset pin
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//|
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STATIC mp_obj_t displayio_fourwire_make_new(const mp_obj_type_t *type, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
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enum { ARG_spi_bus, ARG_command, ARG_chip_select, ARG_reset };
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static const mp_arg_t allowed_args[] = {

‎shared-bindings/displayio/ParallelBus.c‎

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//| .. currentmodule:: displayio
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//|
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//| :class:`ParallelBus` -- Manage updating a display over SPI four wire protocol
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//| ==========================================================================
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//| ==============================================================================
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//|
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//| Manage updating a display over SPI four wire protocol in the background while Python code runs.
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//| It doesn't handle display initialization.
@@ -52,6 +52,13 @@
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//| Create a ParallelBus object associated with the given pins. The bus is inferred from data0
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//| by implying the next 7 additional pins on a given GPIO port.
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//|
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//| :param microcontroller.Pin: The first data pin. The rest are implied
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//| :param microcontroller.Pin command: Data or command pin
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//| :param microcontroller.Pin chip_select: Chip select pin
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//| :param microcontroller.Pin write: Write pin
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//| :param microcontroller.Pin read: Read pin
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//| :param microcontroller.Pin reset: Reset pin
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//|
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STATIC mp_obj_t displayio_parallelbus_make_new(const mp_obj_type_t *type, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
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enum { ARG_data0, ARG_command, ARG_chip_select, ARG_write, ARG_read, ARG_reset };
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static const mp_arg_t allowed_args[] = {

‎shared-bindings/displayio/__init__.c‎

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//|
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//| .. module:: displayio
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//| :synopsis: Native helpers for driving displays
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//| :platform: SAMD21, SAMD51
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//| :platform: SAMD21, SAMD51, nRF52
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//|
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//| The `displayio` module contains classes to manage display output
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//| including synchronizing with refresh rates and partial updating. It does
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//| not include display initialization commands. It should live in a Python
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//| driver for use when a display is connected to a board. It should also be
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//| built into the board init when the board has the display on it.
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//| including synchronizing with refresh rates and partial updating.
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//|
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//| .. warning:: This will be changed before 4.0.0. Consider it very experimental.
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//|
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//| .. method:: release_displays()
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//|
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//| Releases any actively used displays so theis pins can be used again.
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//| Releases any actively used displays so their busses and pins can be used again. This will also
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//| release the builtin display on boards that have one. You will need to reinitialize it yourself
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//| afterwards.
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//|
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STATIC mp_obj_t displayio_release_displays(void) {
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common_hal_displayio_release_displays();

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