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Diff: TextLCD.cpp
- Revision:
- 14:0c32b66b14b8
- Parent:
- 13:24506ba22480
- Child:
- 15:b70ebfffb258
--- a/TextLCD.cpp Sat Feb 09 15:10:36 2013 +0000 +++ b/TextLCD.cpp Sun Feb 10 18:43:51 2013 +0000 @@ -1,6 +1,7 @@ /* mbed TextLCD Library, for a 4-bit LCD based on HD44780 * Copyright (c) 2007-2010, sford, http://mbed.org - * 2013, WH, Added LCD types, fixed LCD address issues, added Cursor and UDCs + * 2013, v01: WH, Added LCD types, fixed LCD address issues, added Cursor and UDCs + * 2013, v02: WH, Added I2C and SPI bus interfaces * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal @@ -28,6 +29,7 @@ PinName d4, PinName d5, PinName d6, PinName d7, LCDType type): _rs(rs), _e(e), _d(d4, d5, d6, d7), + _cs(NC), _type(type) { @@ -40,6 +42,7 @@ TextLCD::TextLCD(I2C *i2c, char deviceAddress, LCDType type) : _rs(NC), _e(NC), _d(NC), + _cs(NC), _i2c(i2c), _type(type) { @@ -57,7 +60,36 @@ } -/** Init the LCD controller + +TextLCD::TextLCD(SPI *spi, PinName cs, LCDType type) : + _rs(NC), _e(NC), _d(NC), + _spi(spi), + _cs(cs), + _type(type) { + + _busType = _SPIBus; + + // Setup the spi for 8 bit data, low steady state clock, + // rising edge capture, with a 500KHz or 1MHz clock rate + _spi->format(8,0); + _spi->frequency(500000); + //_spi.frequency(1000000); + + + // Init the portexpander bus + _lcd_bus = 0x80; + + // write the new data to the portexpander + _setCS(false); + _spi->write(_lcd_bus); + _setCS(true); + + _init(); + +} + + +/* Init the LCD controller * 4-bit mode, number of lines, no cursor etc * Clear display */ @@ -68,16 +100,19 @@ _setEnable(true); _setRS(false); // command mode - wait(0.015); // Wait 15ms to ensure powered up +// wait(0.015); // Wait 15ms to ensure powered up + wait_ms(15); // Wait 15ms to ensure powered up // send "Display Settings" 3 times (Only top nibble of 0x30 as we've got 4-bit bus) for (int i=0; i<3; i++) { _writeByte(0x3); - wait(0.00164); // this command takes 1.64ms, so wait for it +// wait(0.00164); // this command takes 1.64ms, so wait for it + wait_ms(10); // this command takes 1.64ms, so wait for it } _writeByte(0x2); // 4-bit mode - wait(0.000040f); // most instructions take 40us - +// wait(0.000040f); // most instructions take 40us + wait_us(40); // most instructions take 40us + // Display is now in 4-bit mode switch (_type) { case LCD8x1: @@ -144,7 +179,9 @@ void TextLCD::cls() { _writeCommand(0x01); // cls, and set cursor to 0 - wait(0.00164f); // This command takes 1.64 ms +// wait(0.00164f); // This command takes 1.64 ms + wait_ms(10); // The CLS command takes 1.64 ms. + // Since we are not using the Busy flag, Lets be safe and take 10 ms locate(0, 0); } @@ -191,17 +228,27 @@ break; case _I2CBus : - if (value) - _lcd_bus |= D_LCD_E; // Set E bit - else - _lcd_bus &= ~D_LCD_E; // Reset E bit + if (value) + _lcd_bus |= D_LCD_E; // Set E bit + else + _lcd_bus &= ~D_LCD_E; // Reset E bit - // write the new data to the portexpander - _i2c->write(_slaveAddress, &_lcd_bus, 1); + // write the new data to the portexpander + _i2c->write(_slaveAddress, &_lcd_bus, 1); break; case _SPIBus : + if (value) + _lcd_bus |= D_LCD_E; // Set E bit + else + _lcd_bus &= ~D_LCD_E; // Reset E bit + + // write the new data to the portexpander + _setCS(false); + _spi->write(_lcd_bus); + _setCS(true); + break; } } @@ -218,17 +265,27 @@ break; case _I2CBus : - if (value) - _lcd_bus |= D_LCD_RS; // Set RS bit - else - _lcd_bus &= ~D_LCD_RS; // Reset RS bit + if (value) + _lcd_bus |= D_LCD_RS; // Set RS bit + else + _lcd_bus &= ~D_LCD_RS; // Reset RS bit - // write the new data to the portexpander - _i2c->write(_slaveAddress, &_lcd_bus, 1); + // write the new data to the portexpander + _i2c->write(_slaveAddress, &_lcd_bus, 1); break; case _SPIBus : + if (value) + _lcd_bus |= D_LCD_RS; // Set RS bit + else + _lcd_bus &= ~D_LCD_RS; // Reset RS bit + + // write the new data to the portexpander + _setCS(false); + _spi->write(_lcd_bus); + _setCS(true); + break; } @@ -271,28 +328,70 @@ break; case _SPIBus : - break; + + data = value & 0x0F; + if (data & 0x01) + _lcd_bus |= D_LCD_D4; // Set Databit + else + _lcd_bus &= ~D_LCD_D4; // Reset Databit + + if (data & 0x02) + _lcd_bus |= D_LCD_D5; // Set Databit + else + _lcd_bus &= ~D_LCD_D5; // Reset Databit + + if (data & 0x04) + _lcd_bus |= D_LCD_D6; // Set Databit + else + _lcd_bus &= ~D_LCD_D6; // Reset Databit + + if (data & 0x08) + _lcd_bus |= D_LCD_D7; // Set Databit + else + _lcd_bus &= ~D_LCD_D7; // Reset Databit + + // write the new data to the portexpander + _setCS(false); + _spi->write(_lcd_bus); + _setCS(true); + + break; } } +// Set CS line. Only used for SPI bus +void TextLCD::_setCS(bool value) { + + if (value) + _cs = 1; // Set CS pin + else + _cs = 0; // Reset CS pin + +} + + void TextLCD::_writeByte(int value) { // _d = value >> 4; _setData(value >> 4); - wait(0.000040f); // most instructions take 40us +// wait(0.000040f); // most instructions take 40us + wait_us(40); // most instructions take 40us // _e = 0; _setEnable(false); - wait(0.000040f); +// wait(0.000040f); + wait_us(40); // most instructions take 40us // _e = 1; _setEnable(true); // _d = value >> 0; _setData(value >> 0); - wait(0.000040f); +// wait(0.000040f); + wait_us(40); // most instructions take 40us // _e = 0; _setEnable(false); - wait(0.000040f); // most instructions take 40us +// wait(0.000040f); // most instructions take 40us + wait_us(40); // most instructions take 40us // _e = 1; _setEnable(true); }