3 ## OLED Supported Hardware
5 OLED modules using SSD1306 or SH1106 driver ICs, communicating over I2C.
8 | IC driver | Size | Keyboard Platform | Notes |
9 |-----------|--------|-------------------|--------------------------|
10 | SSD1306 | 128x32 | AVR | Primary support |
11 | SSD1306 | 128x64 | AVR | Verified working |
12 | SSD1306 | 128x32 | ARM | |
13 | SH1106 | 128x64 | AVR | No rotation or scrolling |
15 Hardware configurations using ARM-based microcontrollers or different sizes of OLED modules may be compatible, but are untested.
17 !> Warning: This OLED Driver currently uses the new i2c_master driver from split common code. If your split keyboard uses I2C to communicate between sides, this driver could cause an address conflict (serial is fine). Please contact your keyboard vendor and ask them to migrate to the latest split common code to fix this. In addition, the display timeout system to reduce OLED burn-in also uses split common to detect keypresses, so you will need to implement custom timeout logic for non-split common keyboards.
21 To enable the OLED feature, there are three steps. First, when compiling your keyboard, you'll need to set `OLED_DRIVER_ENABLE=yes` in `rules.mk`, e.g.:
24 OLED_DRIVER_ENABLE = yes
27 This enables the feature and the `OLED_DRIVER_ENABLE` define. Then in your `keymap.c` file, you will need to implement the user task call, e.g:
30 #ifdef OLED_DRIVER_ENABLE
31 void oled_task_user(void) {
32 // Host Keyboard Layer Status
33 oled_write_P(PSTR("Layer: "), false);
34 switch (biton32(layer_state)) {
36 oled_write_P(PSTR("Default\n"), false);
39 oled_write_P(PSTR("FN\n"), false);
42 oled_write_P(PSTR("ADJ\n"), false);
45 // Or use the write_ln shortcut over adding '\n' to the end of your string
46 oled_write_ln_P(PSTR("Undefined"), false);
49 // Host Keyboard LED Status
50 uint8_t led_usb_state = host_keyboard_leds();
51 oled_write_P(led_usb_state & (1<<USB_LED_NUM_LOCK) ? PSTR("NUMLCK ") : PSTR(" "), false);
52 oled_write_P(led_usb_state & (1<<USB_LED_CAPS_LOCK) ? PSTR("CAPLCK ") : PSTR(" "), false);
53 oled_write_P(led_usb_state & (1<<USB_LED_SCROLL_LOCK) ? PSTR("SCRLCK ") : PSTR(" "), false);
60 In the default font, ranges in the font file are reserved for a QMK Logo. To Render this logo to the oled screen, use the following code example:
63 static void render_logo(void) {
64 static const char PROGMEM qmk_logo[] = {
65 0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8a,0x8b,0x8c,0x8d,0x8e,0x8f,0x90,0x91,0x92,0x93,0x94,
66 0xa0,0xa1,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7,0xa8,0xa9,0xaa,0xab,0xac,0xad,0xae,0xaf,0xb0,0xb1,0xb2,0xb3,0xb4,
67 0xc0,0xc1,0xc2,0xc3,0xc4,0xc5,0xc6,0xc7,0xc8,0xc9,0xca,0xcb,0xcc,0xcd,0xce,0xcf,0xd0,0xd1,0xd2,0xd3,0xd4,0};
69 oled_write_P(qmk_logo, false);
75 In split keyboards, it is very common to have two OLED displays that each render different content and oriented flipped differently. You can do this by switching which content to render by using the return from `is_keyboard_master()` or `is_keyboard_left()` found in `split_util.h`, e.g:
78 #ifdef OLED_DRIVER_ENABLE
79 oled_rotation_t oled_init_user(oled_rotation_t rotation) {
80 if (!is_keyboard_master())
81 return OLED_ROTATION_180; // flips the display 180 degrees if offhand
85 void oled_task_user(void) {
86 if (is_keyboard_master()) {
87 render_status(); // Renders the current keyboard state (layer, lock, caps, scroll, etc)
89 render_logo(); // Renders a statuc logo
90 oled_scroll_left(); // Turns on scrolling
97 ## Basic Configuration
99 | Define | Default | Description |
100 |------------------------|-------------------|----------------------------------------------------------------------------------------------------------------------------|
101 | `OLED_DISPLAY_ADDRESS` | `0x3C` | The i2c address of the OLED Display |
102 | `OLED_FONT_H` | `"glcdfont.c"` | The font code file to use for custom fonts |
103 | `OLED_FONT_START` | `0` | The starting characer index for custom fonts |
104 | `OLED_FONT_END` | `224` | The ending characer index for custom fonts |
105 | `OLED_FONT_WIDTH` | `6` | The font width |
106 | `OLED_FONT_HEIGHT` | `8` | The font height (untested) |
107 | `OLED_DISABLE_TIMEOUT` | *Not defined* | Disables the built in OLED timeout feature. Useful when implementing custom timeout rules. |
108 | `OLED_IC` | `OLED_IC_SSD1306` | Set to `OLED_IC_SH1106` if you're using the SH1106 OLED controller. |
109 | `OLED_COLUMN_OFFSET` | `0` | (SH1106 only.) Shift output to the right this many pixels.<br />Useful for 128x64 displays centered on a 132x64 SH1106 IC. |
111 ## 128x64 & Custom sized OLED Displays
113 The default display size for this feature is 128x32 and all necessary defines are precalculated with that in mind. We have added a define, `OLED_DISPLAY_128X64`, to switch all the values to be used in a 128x64 display, as well as added a custom define, `OLED_DISPLAY_CUSTOM`, that allows you to provide the necessary values to the driver.
115 |Define |Default |Description |
116 |-----------------------|---------------|-----------------------------------------------------------------|
117 |`OLED_DISPLAY_128X64` |*Not defined* |Changes the display defines for use with 128x64 displays. |
118 |`OLED_DISPLAY_CUSTOM` |*Not defined* |Changes the display defines for use with custom displays.<br />Requires user to implement the below defines. |
119 |`OLED_DISPLAY_WIDTH` |`128` |The width of the OLED display. |
120 |`OLED_DISPLAY_HEIGHT` |`32` |The height of the OLED display. |
121 |`OLED_MATRIX_SIZE` |`512` |The local buffer size to allocate.<br />`(OLED_DISPLAY_HEIGHT / 8 * OLED_DISPLAY_WIDTH)`. |
122 |`OLED_BLOCK_TYPE` |`uint16_t` |The unsigned integer type to use for dirty rendering. |
123 |`OLED_BLOCK_COUNT` |`16` |The number of blocks the display is divided into for dirty rendering.<br />`(sizeof(OLED_BLOCK_TYPE) * 8)`. |
124 |`OLED_BLOCK_SIZE` |`32` |The size of each block for dirty rendering<br />`(OLED_MATRIX_SIZE / OLED_BLOCK_COUNT)`. |
125 |`OLED_COM_PINS` |`COM_PINS_SEQ` |How the SSD1306 chip maps it's memory to display.<br />Options are `COM_PINS_SEQ`, `COM_PINS_ALT`, `COM_PINS_SEQ_LR`, & `COM_PINS_ALT_LR`. |
126 |`OLED_SOURCE_MAP` |`{ 0, ... N }` |Precalculated source array to use for mapping source buffer to target OLED memory in 90 degree rendering. |
127 |`OLED_TARGET_MAP` |`{ 24, ... N }`|Precalculated target array to use for mapping source buffer to target OLED memory in 90 degree rendering. |
130 ### 90 Degree Rotation - Technical Mumbo Jumbo
132 !> Rotation is unsupported on the SH1106.
135 // OLED Rotation enum values are flags
138 OLED_ROTATION_90 = 1,
139 OLED_ROTATION_180 = 2,
140 OLED_ROTATION_270 = 3, // OLED_ROTATION_90 | OLED_ROTATION_180
144 OLED displays driven by SSD1306 drivers only natively support in hard ware 0 degree and 180 degree rendering. This feature is done in software and not free. Using this feature will increase the time to calculate what data to send over i2c to the OLED. If you are strapped for cycles, this can cause keycodes to not register. In testing however, the rendering time on an `atmega32u4` board only went from 2ms to 5ms and keycodes not registering was only noticed once we hit 15ms.
146 90 Degree Rotated Rendering is achieved by using bitwise operations to rotate each 8 block of memory and uses two precalculated arrays to remap buffer memory to OLED memory. The memory map defines are precalculated for remap performance and are calculated based on the OLED Height, Width, and Block Size. For example, in the 128x32 implementation with a `uint8_t` block type, we have a 64 byte block size. This gives us eight 8 byte blocks that need to be rotated and rendered. The OLED renders horizontally two 8 byte blocks before moving down a page, e.g:
149 |---|---|---|---|---|---|
155 However the local buffer is stored as if it was Height x Width display instead of Width x Height, e.g:
158 |---|---|---|---|---|---|
164 So those precalculated arrays just index the memory offsets in the order in which each one iterates its data.
169 // OLED Rotation enum values are flags
172 OLED_ROTATION_90 = 1,
173 OLED_ROTATION_180 = 2,
174 OLED_ROTATION_270 = 3, // OLED_ROTATION_90 | OLED_ROTATION_180
177 // Initialize the OLED display, rotating the rendered output based on the define passed in.
178 // Returns true if the OLED was initialized successfully
179 bool oled_init(oled_rotation_t rotation);
181 // Called at the start of oled_init, weak function overridable by the user
182 // rotation - the value passed into oled_init
183 // Return new oled_rotation_t if you want to override default rotation
184 oled_rotation_t oled_init_user(oled_rotation_t rotation);
186 // Clears the display buffer, resets cursor position to 0, and sets the buffer to dirty for rendering
187 void oled_clear(void);
189 // Renders the dirty chunks of the buffer to OLED display
190 void oled_render(void);
192 // Moves cursor to character position indicated by column and line, wraps if out of bounds
193 // Max column denoted by 'oled_max_chars()' and max lines by 'oled_max_lines()' functions
194 void oled_set_cursor(uint8_t col, uint8_t line);
196 // Advances the cursor to the next page, writing ' ' if true
197 // Wraps to the begining when out of bounds
198 void oled_advance_page(bool clearPageRemainder);
200 // Moves the cursor forward 1 character length
201 // Advance page if there is not enough room for the next character
202 // Wraps to the begining when out of bounds
203 void oled_advance_char(void);
205 // Writes a single character to the buffer at current cursor position
206 // Advances the cursor while writing, inverts the pixels if true
207 // Main handler that writes character data to the display buffer
208 void oled_write_char(const char data, bool invert);
210 // Writes a string to the buffer at current cursor position
211 // Advances the cursor while writing, inverts the pixels if true
212 void oled_write(const char *data, bool invert);
214 // Writes a string to the buffer at current cursor position
215 // Advances the cursor while writing, inverts the pixels if true
216 // Advances the cursor to the next page, wiring ' ' to the remainder of the current page
217 void oled_write_ln(const char *data, bool invert);
219 // Writes a PROGMEM string to the buffer at current cursor position
220 // Advances the cursor while writing, inverts the pixels if true
221 // Remapped to call 'void oled_write(const char *data, bool invert);' on ARM
222 void oled_write_P(const char *data, bool invert);
224 // Writes a PROGMEM string to the buffer at current cursor position
225 // Advances the cursor while writing, inverts the pixels if true
226 // Advances the cursor to the next page, wiring ' ' to the remainder of the current page
227 // Remapped to call 'void oled_write_ln(const char *data, bool invert);' on ARM
228 void oled_write_ln_P(const char *data, bool invert);
230 // Can be used to manually turn on the screen if it is off
231 // Returns true if the screen was on or turns on
234 // Can be used to manually turn off the screen if it is on
235 // Returns true if the screen was off or turns off
238 // Basically it's oled_render, but with timeout management and oled_task_user calling!
239 void oled_task(void);
241 // Called at the start of oled_task, weak function overridable by the user
242 void oled_task_user(void);
244 // Scrolls the entire display right
245 // Returns true if the screen was scrolling or starts scrolling
246 // NOTE: display contents cannot be changed while scrolling
247 bool oled_scroll_right(void);
249 // Scrolls the entire display left
250 // Returns true if the screen was scrolling or starts scrolling
251 // NOTE: display contents cannot be changed while scrolling
252 bool oled_scroll_left(void);
254 // Turns off display scrolling
255 // Returns true if the screen was not scrolling or stops scrolling
256 bool oled_scroll_off(void);
258 // Returns the maximum number of characters that will fit on a line
259 uint8_t oled_max_chars(void);
261 // Returns the maximum number of lines that will fit on the OLED
262 uint8_t oled_max_lines(void);
265 !> Scrolling and rotation are unsupported on the SH1106.
267 ## SSD1306.h driver conversion guide
269 |Old API |Recommended New API |
270 |---------------------------|-----------------------------------|
271 |`struct CharacterMatrix` |*removed - delete all references* |
272 |`iota_gfx_init` |`oled_init` |
273 |`iota_gfx_on` |`oled_on` |
274 |`iota_gfx_off` |`oled_off` |
275 |`iota_gfx_flush` |`oled_render` |
276 |`iota_gfx_write_char` |`oled_write_char` |
277 |`iota_gfx_write` |`oled_write` |
278 |`iota_gfx_write_P` |`oled_write_P` |
279 |`iota_gfx_clear_screen` |`oled_clear` |
280 |`matrix_clear` |*removed - delete all references* |
281 |`matrix_write_char_inner` |`oled_write_char` |
282 |`matrix_write_char` |`oled_write_char` |
283 |`matrix_write` |`oled_write` |
284 |`matrix_write_ln` |`oled_write_ln` |
285 |`matrix_write_P` |`oled_write_P` |
286 |`matrix_write_ln_P` |`oled_write_ln_P` |
287 |`matrix_render` |`oled_render` |
288 |`iota_gfx_task` |`oled_task` |
289 |`iota_gfx_task_user` |`oled_task_user` |