Display driver for Sharp's range of SPI-driven memory LCD's, leveraging the power of asynchronous transfers. Currently supports LS013B7DH03, but easily extendable to other models as well.
Dependents: memLCD-Demo memLCD-Demo memLCD-Demo MemLCD-Temperature-Humidity-Demo ... more
Information
All examples in this repo are considered EXPERIMENTAL QUALITY, meaning this code has been created as one-off proof-of-concept and is suitable as a demonstration for experimental purposes only. This code will not be regularly maintained by Silicon Labs and there is no guarantee that these projects will work across all environments, SDK versions and hardware.
Caution
This library builds upon the asynchronous SPI interface provided by mbed, but not all platforms currently support this. So, make sure your platform is capable of asynchronous SPI (all Silicon Labs platforms are), otherwise you will get compiler errors!
Usage
The library is purposefully quite simple to use. To set it up, you initialize an SPI object and the required I/O pins, and call the library constructor with those. Make sure the display is powered on, enabled, and the inversion mode is set to external (EXTMODE is high).
setup
#define SCK PD2 #define MOSI PD0 DigitalOut CS(PD3); DigitalOut EXTCOM(PC4); SPI displaySPI(MOSI, NC, SCK); silabs::LS013B7DH03 display(&displaySPI, &CS, &EXTCOM);
You should also swap out the pin names for the relevant names on your platform.
After setup, you usually want to clear any static information left on the screen. To do that, you would call clearImmediate, and optionally provide a callback. The callback will get called when the clearing operation is complete and the display has been cleared. In this example, refreshCallback sets a global boolean 'refreshed' to true when called.
clearing the display
refreshed = false; int result = display.clearImmediate(refreshCallback); if(result == LS013B7DH03_OK) { while(refreshed == false) sleep(); } else { printf("Display error: %d", result); }
Of course, instead of sleeping while the display is clearing, you could also just continue with the program, and check back whether the callback happened or not.
Then comes the fun part, actually writing stuff on the display! Since the display only supports one-way communication (i.e. you cannot read from it), it uses an internal frame buffer in RAM. So, to actually display something on the LCD, two steps need to happen: writing to the pixel buffer, and at the very end writing the pixel buffer to the LCD.
Pixelbuffer operations
The MemoryLCD library builds upon Simon Ford's TextDisplay library, which means you can use all of that functionality. Even printf is supported!
most important display operations
// Set one pixel at x=10, y=40 to the color White display.pixel(10,40,White); // print "I love mbed" at the character position x=4, y=5 // i.e. starting on row 5, 4 characters from the left border display.locate(4,5); display.printf("I love mbed!"); // show a bitmap at a given location // Constraints: bitmap is 8-bit, MSB first, 1 bit per pixel. Width, height and starting coordinates must be divisible by 8. // This example: show a bitmap which is 128 pixels wide and high, and start at location 0,0. display.showBMP(&mbed_logo, 128, 128, 0, 0); //Draw a line (really a 1px wide rectangle) from (4,10) until (4,15) display.fill(4, 10, 1, 5, White);
Updating the LCD
Updating the LCD (i.e. moving the framebuffer to the display) happens much the same way as clearing it: asynchronously. To start the update, you call update() on the display, optionally providing a callback to be called after the whole update has happened. In the example below, refreshCallback sets a global boolean 'refreshed' to true when called. Signature: void refreshCallback(void);
updating the display
refreshed = false; int result = display.update(refreshCallback); if(result == LS013B7DH03_OK) { while(refreshed == false) sleep(); } else { printf("Display error: %d", result); }
Full example
example program
#include "LS013B7DH03.h" #include "mbed_logo.h" /******************** Define I/O *****************************/ DigitalOut myled(LED1); #define SCK PD2 #define MOSI PD0 DigitalOut CS(PD3); DigitalOut EXTCOM(PC4); DigitalOut EXTMODE(PD4); DigitalOut DISP(PD5); SPI displaySPI(MOSI, NC, SCK); silabs::LS013B7DH03 display(&displaySPI, &CS, &EXTCOM); /******************** Define Timers *****************************/ LowPowerTicker timeKeeping; /***************** Define global variables **********************/ #define INIT_SECONDS 17600 volatile uint32_t prevSeconds = INIT_SECONDS, seconds = INIT_SECONDS; volatile bool refreshed = false; /***************** Define callback handlers *********************/ void secondsCallback(void); void refreshCallback(void); void secondsCallback(void) { seconds++; } /** * Callback for refresh completion */ void refreshCallback(void) { refreshed = true; } /*************************** MAIN *******************************/ int main() { // Enable the LCD EXTMODE = 1; DISP = 1; // Start generating the 1Hz call for keeping time timeKeeping.attach(&secondsCallback, 1.0f); // Reset the LCD to a blank state. (All white) refreshed = false; display.clearImmediate(refreshCallback); while(refreshed == false) sleep(); printf("Initialization done! \n"); // Apply mbed logo bitmap to the pixel buffer display.showBMP((uint8_t*)mbed_enabled_logo, 128, 128, 0, 0); display.printf("I like MBED!"); // Push update to the display refreshed = false; display.update(refreshCallback); // Sleep while doing the transmit while(refreshed == false) sleep(); // Go into clock mode while(1) { sleep(); // In clock mode, only update once per second if(prevSeconds != seconds) { display.locate(4,15); display.printf("%02d:%02d:%02d", (seconds / 1200) % 24, (seconds / 60) % 60, seconds % 60); if(refreshed == true) { prevSeconds = seconds; refreshed = false; display.update(refreshCallback); } } } }
Datasheet
Datasheet for the LCD (hosted by Mouser)
LS013B7DH03.h@11:0f8ae10b308d, 2015-08-12 (annotated)
- Committer:
- stevew817
- Date:
- Wed Aug 12 14:06:07 2015 +0000
- Revision:
- 11:0f8ae10b308d
- Parent:
- 3:c34c3e4e33fc
Implement Paul Staron's enhancements to the display driver classes, from https://developer.mbed.org/users/star297/code/MemoryLCD/rev/b64f87859c57
Who changed what in which revision?
User | Revision | Line number | New contents of line |
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Steven Cooreman |
0:a0faa86660d4 | 1 | /***************************************************************************//** |
Steven Cooreman |
0:a0faa86660d4 | 2 | * @file LS013B7DH03.h |
Steven Cooreman |
0:a0faa86660d4 | 3 | * @brief Driver class for the Sharp LS013B7DH03 memory LCD on some kits. |
Steven Cooreman |
0:a0faa86660d4 | 4 | ******************************************************************************* |
Steven Cooreman |
0:a0faa86660d4 | 5 | * @section License |
Steven Cooreman |
0:a0faa86660d4 | 6 | * <b>(C) Copyright 2015 Silicon Labs, http://www.silabs.com</b> |
Steven Cooreman |
0:a0faa86660d4 | 7 | ******************************************************************************* |
Steven Cooreman |
0:a0faa86660d4 | 8 | * |
Steven Cooreman |
0:a0faa86660d4 | 9 | * Permission is granted to anyone to use this software for any purpose, |
Steven Cooreman |
0:a0faa86660d4 | 10 | * including commercial applications, and to alter it and redistribute it |
Steven Cooreman |
0:a0faa86660d4 | 11 | * freely, subject to the following restrictions: |
Steven Cooreman |
0:a0faa86660d4 | 12 | * |
Steven Cooreman |
0:a0faa86660d4 | 13 | * 1. The origin of this software must not be misrepresented; you must not |
Steven Cooreman |
0:a0faa86660d4 | 14 | * claim that you wrote the original software. |
Steven Cooreman |
0:a0faa86660d4 | 15 | * 2. Altered source versions must be plainly marked as such, and must not be |
Steven Cooreman |
0:a0faa86660d4 | 16 | * misrepresented as being the original software. |
Steven Cooreman |
0:a0faa86660d4 | 17 | * 3. This notice may not be removed or altered from any source distribution. |
Steven Cooreman |
0:a0faa86660d4 | 18 | * |
Steven Cooreman |
0:a0faa86660d4 | 19 | * DISCLAIMER OF WARRANTY/LIMITATION OF REMEDIES: Silicon Labs has no |
Steven Cooreman |
0:a0faa86660d4 | 20 | * obligation to support this Software. Silicon Labs is providing the |
Steven Cooreman |
0:a0faa86660d4 | 21 | * Software "AS IS", with no express or implied warranties of any kind, |
Steven Cooreman |
0:a0faa86660d4 | 22 | * including, but not limited to, any implied warranties of merchantability |
Steven Cooreman |
0:a0faa86660d4 | 23 | * or fitness for any particular purpose or warranties against infringement |
Steven Cooreman |
0:a0faa86660d4 | 24 | * of any proprietary rights of a third party. |
Steven Cooreman |
0:a0faa86660d4 | 25 | * |
Steven Cooreman |
0:a0faa86660d4 | 26 | * Silicon Labs will not be liable for any consequential, incidental, or |
Steven Cooreman |
0:a0faa86660d4 | 27 | * special damages, or any other relief, or for any claim by any third party, |
Steven Cooreman |
0:a0faa86660d4 | 28 | * arising from your use of this Software. |
Steven Cooreman |
0:a0faa86660d4 | 29 | * |
Steven Cooreman |
0:a0faa86660d4 | 30 | ******************************************************************************/ |
Steven Cooreman |
0:a0faa86660d4 | 31 | |
Steven Cooreman |
0:a0faa86660d4 | 32 | #ifndef SILABS_LS013B7DH03_H |
Steven Cooreman |
0:a0faa86660d4 | 33 | #define SILABS_LS013B7DH03_H |
Steven Cooreman |
0:a0faa86660d4 | 34 | |
Steven Cooreman |
0:a0faa86660d4 | 35 | #include "platform.h" |
Steven Cooreman |
0:a0faa86660d4 | 36 | #include <mbed.h> |
Steven Cooreman |
0:a0faa86660d4 | 37 | #include "LCDSettings.h" |
Steven Cooreman |
0:a0faa86660d4 | 38 | #include "BufferedDisplay.h" |
Steven Cooreman |
0:a0faa86660d4 | 39 | |
Steven Cooreman |
0:a0faa86660d4 | 40 | typedef void (*cbptr_t)(void); |
Steven Cooreman |
0:a0faa86660d4 | 41 | |
Steven Cooreman |
0:a0faa86660d4 | 42 | #define LS013B7DH03_ERROR_BUSY -1 |
Steven Cooreman |
0:a0faa86660d4 | 43 | #define LS013B7DH03_ERROR_SPI_BUSY -2 |
Steven Cooreman |
0:a0faa86660d4 | 44 | #define LS013B7DH03_NO_ACTION -3 |
Steven Cooreman |
0:a0faa86660d4 | 45 | #define LS013B7DH03_ERROR_ARGUMENT -4 |
Steven Cooreman |
0:a0faa86660d4 | 46 | #define LS013B7DH03_OK 0 |
Steven Cooreman |
0:a0faa86660d4 | 47 | |
Steven Cooreman |
0:a0faa86660d4 | 48 | typedef enum { |
Steven Cooreman |
0:a0faa86660d4 | 49 | IDLE, // No operation currently ongoing |
Steven Cooreman |
0:a0faa86660d4 | 50 | CLEARING, // In the process of clearing the display |
Steven Cooreman |
0:a0faa86660d4 | 51 | WRITING, // In the process of sending a display update |
Steven Cooreman |
0:a0faa86660d4 | 52 | WAIT_CLEAR, // Going to clear after CS pin timeout |
Steven Cooreman |
0:a0faa86660d4 | 53 | WAIT_WRITE, // Going to write after CS pin timeout |
Steven Cooreman |
0:a0faa86660d4 | 54 | TRANSFERS_DONE, // Last transfer in progress |
Steven Cooreman |
0:a0faa86660d4 | 55 | DONE // Done with transmission, waiting for CS pin to become high |
Steven Cooreman |
0:a0faa86660d4 | 56 | } LS013B7DH03_state_t; |
Steven Cooreman |
0:a0faa86660d4 | 57 | |
Steven Cooreman |
0:a0faa86660d4 | 58 | namespace silabs { |
Steven Cooreman |
1:6332f3383fb6 | 59 | class LS013B7DH03 : public BufferedDisplay { |
Steven Cooreman |
2:2f10f00fe56c | 60 | |
Steven Cooreman |
0:a0faa86660d4 | 61 | public: |
Steven Cooreman |
0:a0faa86660d4 | 62 | |
Steven Cooreman |
0:a0faa86660d4 | 63 | LS013B7DH03(SPI * spi, DigitalOut * CS, DigitalOut * ExtCom, const char *name=NULL); |
Steven Cooreman |
0:a0faa86660d4 | 64 | |
Steven Cooreman |
0:a0faa86660d4 | 65 | /** |
Steven Cooreman |
0:a0faa86660d4 | 66 | * Call this function to push all changes to the display |
Steven Cooreman |
0:a0faa86660d4 | 67 | */ |
Steven Cooreman |
0:a0faa86660d4 | 68 | int update( cbptr_t callback = NULL ); |
Steven Cooreman |
0:a0faa86660d4 | 69 | |
Steven Cooreman |
0:a0faa86660d4 | 70 | /** |
Steven Cooreman |
0:a0faa86660d4 | 71 | * Immediately clear the display: set pixel buffer to zero and clear out the display. |
Steven Cooreman |
0:a0faa86660d4 | 72 | */ |
Steven Cooreman |
0:a0faa86660d4 | 73 | int clearImmediate( cbptr_t callback = NULL ); |
Steven Cooreman |
0:a0faa86660d4 | 74 | |
Steven Cooreman |
0:a0faa86660d4 | 75 | /** |
Steven Cooreman |
0:a0faa86660d4 | 76 | * Function to test display buffer |
Steven Cooreman |
0:a0faa86660d4 | 77 | */ |
Steven Cooreman |
0:a0faa86660d4 | 78 | int showDemo(); |
Steven Cooreman |
0:a0faa86660d4 | 79 | |
Steven Cooreman |
0:a0faa86660d4 | 80 | /** |
Steven Cooreman |
2:2f10f00fe56c | 81 | * Function to get internal refresh counter |
Steven Cooreman |
0:a0faa86660d4 | 82 | */ |
Steven Cooreman |
0:a0faa86660d4 | 83 | uint32_t getRefreshTicks(); |
Steven Cooreman |
0:a0faa86660d4 | 84 | |
Steven Cooreman |
0:a0faa86660d4 | 85 | protected: |
Steven Cooreman |
0:a0faa86660d4 | 86 | mbed::SPI *_spi; |
Steven Cooreman |
0:a0faa86660d4 | 87 | mbed::DigitalOut *_EXTCOM; |
Steven Cooreman |
0:a0faa86660d4 | 88 | mbed::DigitalOut *_CS; |
Steven Cooreman |
0:a0faa86660d4 | 89 | |
Steven Cooreman |
0:a0faa86660d4 | 90 | mbed::LowPowerTicker _displayToggler; |
Steven Cooreman |
0:a0faa86660d4 | 91 | mbed::LowPowerTimeout _csTimeout; |
Steven Cooreman |
0:a0faa86660d4 | 92 | |
Steven Cooreman |
2:2f10f00fe56c | 93 | event_callback_t _internalEventCallback; |
Steven Cooreman |
0:a0faa86660d4 | 94 | volatile uint32_t _refreshCount; |
Steven Cooreman |
0:a0faa86660d4 | 95 | uint8_t _lcdPolarity; |
Steven Cooreman |
0:a0faa86660d4 | 96 | LS013B7DH03_state_t _state; |
Steven Cooreman |
0:a0faa86660d4 | 97 | cbptr_t _completionCallbackPtr; |
Steven Cooreman |
0:a0faa86660d4 | 98 | volatile uint32_t _rowCount; |
Steven Cooreman |
0:a0faa86660d4 | 99 | uint8_t _cmd[2 + (DISPLAY_WIDTH / DISPLAY_BUFFER_TYPE_SIZE * sizeof(DISPLAY_BUFFER_TYPE))]; |
Steven Cooreman |
0:a0faa86660d4 | 100 | |
Steven Cooreman |
0:a0faa86660d4 | 101 | /** |
Steven Cooreman |
0:a0faa86660d4 | 102 | * Callback handler for internal SPI transfers. |
Steven Cooreman |
0:a0faa86660d4 | 103 | */ |
Steven Cooreman |
0:a0faa86660d4 | 104 | void _cbHandler( int event ); |
Steven Cooreman |
0:a0faa86660d4 | 105 | |
Steven Cooreman |
0:a0faa86660d4 | 106 | /** |
Steven Cooreman |
0:a0faa86660d4 | 107 | * Callback handler for internal SPI transfers triggered by timeout. |
Steven Cooreman |
0:a0faa86660d4 | 108 | */ |
Steven Cooreman |
0:a0faa86660d4 | 109 | void _cbHandlerTimeout( void ); |
Steven Cooreman |
0:a0faa86660d4 | 110 | |
Steven Cooreman |
0:a0faa86660d4 | 111 | /** |
Steven Cooreman |
2:2f10f00fe56c | 112 | * Call this function at 55 ~ 65 Hz to keep the display from losing contrast. |
Steven Cooreman |
0:a0faa86660d4 | 113 | */ |
Steven Cooreman |
0:a0faa86660d4 | 114 | void toggle(); |
Steven Cooreman |
0:a0faa86660d4 | 115 | }; |
Steven Cooreman |
0:a0faa86660d4 | 116 | |
Steven Cooreman |
0:a0faa86660d4 | 117 | } // namespace silabs |
Steven Cooreman |
0:a0faa86660d4 | 118 | |
Steven Cooreman |
0:a0faa86660d4 | 119 | #endif //SILABS_LS013B7DH03_H |