mirror of
https://github.com/RIOT-OS/RIOT.git
synced 2024-12-29 04:50:03 +01:00
b253f61a7f
- Passing RIOT-OS specific data as user_ptr - Added necessary macros to Makefile.dep - Added missing explicit dependency to xtimer module - Renamed u8g2_riotos.c to more appropriate u8x8_riotos.c - Added u8x8_riotos.h with the RIOT-OS specific functionality - Removed the now-obsolete patch of U8g2 - Other minor fixes
56 lines
2.2 KiB
Markdown
56 lines
2.2 KiB
Markdown
# U8g2
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## Introduction
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[U8g2](https://github.com/olikraus/u8g2) is a monochrome graphics library for LCDs and OLEDs. It contains both drivers and high-level drawing routines.
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The library is originally written for Arduino boards, but it runs just fine on other platforms, as long as the right drivers are available.
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## Usage
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Just put `USEPKG += u8g2` in your Makefile and `#include "u8g2.h"` into your code. Refer to the [U8g2 wiki](https://github.com/olikraus/u8g2/wiki) for more information on the API.
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## RIOT-OS interface
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This adds an interface for RIOT-OS.
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The following two callbacks add support for the included drivers via I2C and SPI peripherals:
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* `u8x8_byte_hw_spi_riotos`
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* `u8x8_byte_hw_i2c_riotos`
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For timing and GPIO related operations, the following callback is available.
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* `u8x8_gpio_and_delay_riotos`
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These methods require a structure containing peripheral information (`u8x8_riotos_t`), that is set using the `u8g2_SetUserPtr` function. This structure contains the peripheral and pin mapping.
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If the above interface is not sufficient, it is still possible to write a dedicated interface by (re-)implementing the methods above. Refer to the [U8g2 wiki](https://github.com/olikraus/u8g2/wiki) for more information.
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### Example
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```c
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u8g2_t u8g2;
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u8x8_riotos_t user_data =
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{
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.device_index = SPI_DEV(0),
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.pin_cs = GPIO_PIN(PA, 0),
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.pin_dc = GPIO_PIN(PA, 1),
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.pin_reset = GPIO_PIN(PA, 2)
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};
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u8g2_SetUserPtr(&u8g2, &user_data);
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u8g2_Setup_ssd1306_128x64_noname_1(&u8g2, U8G2_R0, u8x8_byte_riotos_hw_spi, u8x8_gpio_and_delay_riotos);
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```
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## Virtual displays
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For targets without an I2C or SPI, virtual displays are available. These displays are part of U8g2, but are not compiled by default.
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* By adding `USEMODULE += u8g2_utf8`, a terminal display is used as virtual display, using UTF8 block characters that are printed to stdout.
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* By adding `USEMODULE += u8g2_sdl`, a SDL virtual display will be used. This is only available on native targets that have SDL installed. It uses `sdl2-config` to find the headers and libraries. Note that RIOT-OS builds 32-bit binaries and requires 32-bit SDL libraries.
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### Example
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```c
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u8g2_t u8g2;
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u8g2_SetupBuffer_Utf8(&u8g2, U8G2_R0);
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```
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