10Hz GPS, MEgasquirt, SD Card, ADxl345, 20x4 LCD datalogger
Dependencies: ADXL345 10HzGPSdatalogger mbed
TextLCD.cpp
- Committer:
- jpnovak
- Date:
- 2015-11-28
- Revision:
- 0:b8d7df90819e
File content as of revision 0:b8d7df90819e:
/* draft mbed TextLCD * (c) 2007/8, sford */ #include "TextLCD.h" #include "mbed.h" using namespace mbed; /* * useful info found at http://www.a-netz.de/lcd.en.php * * * Initialisation * ============== * * After attaching the supply voltage/after a reset, the display needs to be brought in to a defined state * * - wait approximately 15 ms so the display is ready to execute commands * - Execute the command 0x30 ("Display Settings") three times (wait 1,64ms after each command, the busy flag cannot be queried now). * - The display is in 8 bit mode, so if you have only connected 4 data pins you should only transmit the higher nibble of each command. * - If you want to use the 4 bit mode, now you can execute the command to switch over to this mode now. * - Execute the "clear display" command * * Timing * ====== * * Nearly all commands transmitted to the display need 40us for execution. * Exceptions are the commands "Clear Display and Reset" and "Set Cursor to Start Position" * These commands need 1.64ms for execution. These timings are valid for all displays working with an * internal clock of 250kHz. But I do not know any displays that use other frequencies. Any time you * can use the busy flag to test if the display is ready to accept the next command. * * _e is kept high apart from calling clock * _rw is kept 0 (write) apart from actions that uyse it differently * _rs is set by the data/command writes */ //wait(0.05); TextLCD::TextLCD(PinName rs, PinName rw, PinName e, PinName d0, PinName d1, PinName d2, PinName d3, int columns, int rows) : _rw(rw), _rs(rs), _e(e), _d(d0, d1, d2, d3), _columns(columns), _rows(rows) { _rows = 4; _columns = 20; wait(0.05); _rw = 0; _e = 1; _rs = 0; // command mode wait(0.05); // Should theoretically wait 15ms, but most things will be powered up pre-reset // so i'll disable that for the minute. If implemented, could wait 15ms post reset // instead // wait(0.015); // send "Display Settings" 3 times (Only top nibble of 0x30 as we've got 4-bit bus) for(int i=0; i<3; i++) { writeNibble(0x3); wait(0.005); // this command takes 1.64ms, so wait for it } wait(0.1); writeNibble(0x2); // 4-bit mode wait(0.001); writeCommand(0x28); // Function set 001 BW N F - - wait(0.001); writeCommand(0x0C); wait(0.001); writeCommand(0x6); // Cursor Direction and Display Shift : 0000 01 CD S (CD 0-left, 1-right S(hift) 0-no, 1-yes cls(); } int TextLCD::_putc(int value) { if(value == '\n') { newline(); } else { writeData(value); } return value; } int TextLCD::_getc() { return 0; } void TextLCD::newline() { _column = 0; _row++; if(_row >= _rows) { _row = 0; } locate(_column, _row); } void TextLCD::locate(int column, int row) { /* if(column < 0 || column >= _columns || row < 0 || row >= _rows) { ERROR("locate(%d,%d) out of range on %dx%d display", column, row, _columns, _rows); return; }*/ _row = row; _column = column; int address=0; if (_rows > 2) { // row 0 : 0x0->0x13 // row 1 : 0x40->0x53 // row 2 : 0x14->0x27 // row 3 : 0x54->0x67 switch (_row) { case (0) : address = 0x80 + _column; break; case (1) : address = 0xc0 + _column; break; case (2) : address = 0x94 + _column; break; case (3) : address = 0xd4 + _column; break; } } else { // memory starts at 0x80, and is 40 chars long per row address = 0x80 + (_row * 40) + _column; } writeCommand(address); } void TextLCD::rows(int rows) { _rows = rows; } void TextLCD::columns(int columns) { _columns = columns; } void TextLCD::cls() { writeCommand(0x01); // Clear Display wait(0.00164f); // This command takes 1.64 ms locate(0, 0); } void TextLCD::reset() { cls(); } void TextLCD::clock() { wait(0.00010); _e = 0; wait(0.00010); // most instructions take 40us _e = 1; } void TextLCD::writeNibble(int value) { _d = value; clock(); } void TextLCD::writeByte(int value) { writeNibble(value >> 4); writeNibble(value >> 0); } void TextLCD::writeCommand(int command) { _rs = 0; writeByte(command); } void TextLCD::writeData(int data) { _rs = 1; writeByte(data); _column++; if(_column >= _columns) { newline(); } }