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/*
* This file is subject to the terms of the GFX License. If a copy of
* the license was not distributed with this file, you can obtain one at:
*
* http://ugfx.org/license.html
*/
#ifndef _GDISP_LLD_BOARD_H
#define _GDISP_LLD_BOARD_H
#include "board_uext.h"
/*
* NOTE: This board file is for an SSD1306 running in I2C mode
* You will need to use a different board file for an SSD1306 running in SPI mode
*/
#define I2C_ADDRESS (0x78/2) // SSD1306 supports either 0x78 or 0x7A (including the write bit)
#define I2C_RATE 400000 // 400kHz is I2C FAST mode
// The various methods of driving the I2C interface
#define I2C_METHOD_CHIBIOS 3
// The various supported CPU's
#define CPU_AT91 1
// What methods are we using in this file
#define I2C_METHOD I2C_METHOD_CHIBIOS
#define CPU_METHOD CPU_AT91
// If using SPI_METHOD_CHIBIOS the CPU specific i2cconfig structure must be defined for your CPU
#if CPU_METHOD == CPU_AT91
#define I2C_CONFIG_REGISTER ((((MCK/I2C_RATE/2 - 3)>>8)<<16)|(((MCK/I2C_RATE/2 - 3)&0xFF)<<8)|(((MCK/I2C_RATE/2 - 3)&0xFF)<<0)) // For AT91SAM7: 8bit, CPOL=1, NCPHA = 0, ClockPhase=0, SCLK = 48Mhz/8 = 6MHz
#if I2C_METHOD == I2C_METHOD_CHIBIOS
// ChibiOS - Yuck! This structure is different on each platform.
// This is the one for the AT91
static const I2CConfig i2cconfig = {
I2C_CONFIG_REGISTER
};
#endif
#else
#error "SSD1306: Unsupported CPU"
#endif
//---------------------------------------------------------------------
/*
* Pin connection for the display to the UEXT connector:
*
* DISPLAY VCC UEXT PIN 1 (3.3V)
* DISPLAY GND UEXT PIN 2 (GND)
* DISPLAY SCL UEXT PIN 5 (SCL)
* DISPLAY SDA UEXT PIN 6 (SDA)
*/
#if I2C_METHOD == I2C_METHOD_CHIBIOS
/* ChibiOS can't send a separate data prefix byte in the same transaction as the real data.
* Nor does it support an address prefix to the data (such as an EEPROM would use).
* Instead we tell the driver to put it into the RAM buffer at the beginning of each page (Yuck!).
*
* Prefix bytes:
* 0x40 means all following bytes in this transaction go into the GDRAM.
* 0x00 means the following byte (singular) is a command byte.
*/
#define SSD1306_PAGE_PREFIX 0x40
#define I2C_INIT()
#define I2C_GETBUS() { \
i2cAcquireBus(UEXT_I2C); \
i2cStart(UEXT_I2C, &i2cconfig); \
}
#define I2C_RELEASEBUS() { \
i2cStop(UEXT_I2C); \
i2cReleaseBus(UEXT_I2C); \
}
#define I2C_WAITCOMPLETE()
#define I2C_WRITECMDBYTE(cmd) { \
uint8_t data[2]; \
data[0] = 0; \
data[1] = cmd; \
i2cMasterTransmitTimeout (UEXT_I2C, I2C_ADDRESS, data, 2, 0, 0, TIME_INFINITE); \
}
#define I2C_WRITEBYTES(pdata, len) i2cMasterTransmitTimeout (UEXT_I2C, I2C_ADDRESS, pdata, length, 0, 0, TIME_INFINITE)
#else
#error "SSD1306 board file: Unsupported I2C method"
#endif
static GFXINLINE void init_board(GDisplay *g) {
(void) g;
I2C_INIT();
}
static GFXINLINE void post_init_board(GDisplay *g) {
(void) g;
}
static GFXINLINE void setpin_reset(GDisplay *g, gBool state) {
(void) g;
(void) state;
}
static GFXINLINE void set_backlight(GDisplay *g, uint8_t percent) {
(void) g;
(void) percent;
}
static GFXINLINE void acquire_bus(GDisplay *g) {
(void) g;
I2C_GETBUS();
}
static GFXINLINE void release_bus(GDisplay *g) {
(void) g;
I2C_WAITCOMPLETE();
I2C_RELEASEBUS();
}
static GFXINLINE void write_cmd(GDisplay *g, uint8_t cmd) {
(void) g;
I2C_WAITCOMPLETE();
// Command mode please
I2C_WRITECMDBYTE(cmd);
}
static GFXINLINE void write_data(GDisplay *g, uint8_t* data, uint16_t length) {
(void) g;
I2C_WAITCOMPLETE();
// Data mode please
I2C_WRITEBYTES(data, length);
}
#endif /* _GDISP_LLD_BOARD_H */
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