Simon Ford
/
displays
EA_QVGALCD.cpp
- Committer:
- simon
- Date:
- 2009-09-15
- Revision:
- 0:cc002f2fad97
File content as of revision 0:cc002f2fad97:
/* mbed Embedded Artists QVGA LCD Display Library * Copyright (c) 2007-2009 sford * Released under the MIT License: http://mbed.org/license/mit */ #include "EA_QVGALCD.h" EA_QVGALCD::EA_QVGALCD(PinName mosi, PinName miso, PinName sclk, PinName cs, PinName rst) : _spi(mosi, miso, sclk), _cs(cs), _rst(rst) { _spi.frequency(15000000); _spi.format(9); _cs = 1; _rst = 0; wait(0.001); _rst = 1; wait(0.001); // 3-wire SPI Format (see 7.1 c) // ================= // // The 3-wire spi format uses 9-bit messages of the form: // // [Data/nControl D7 D6 D5 D4 D3 D2 D1 D0] // (first) (last) // // Most commands and data are 16-bit, so are achieved by sending two // command messages, [ CommandMSB | CommandLSB ], or two data messages // [ DataMSB | DataLSB ]. // // Controlling the Display // ======================= // // The Index Register is used to setup which configuration register is // modified. This address is changed by sending a command message: // // command [ 0 | index[7:0] ] // // The data that follows update the register. // // // 0x07 - Display Control // ====================== // // [ 0 0 0 PT1 PT0 VLE2 VLE1 SPT | 0 0 GON DTE CM 0 D1 D0 ] // where: // PT[1:0] - ? (0) // VLE[2:1] - ? (0) // SPT - ? (0) // CM - 8 colour mode enable // GON - 0 = Gate-off level VGH // DTE - 0 = All gate outputs become VGL // 1 = Selected gate outputs become VGH // D[1:0] - D1 = Display enable // D0 = Display operating // 15.5 On Sequence // // -> Set R07h: GON =1, DTE = 0, D[1:0] = 01 _cs = 0; config(0x7 , 1 << 5 // GON | 0 << 4 // DTE | 0 << 3 // CM | 1 << 0 // D[1:0] = 01 - operate, but disp off ); // -> Set R00h to 0001h // R00h [ 00000000 | 0000000 OSCEN ] // OSCEN - 1 = oscillator enabled config(0x0, 1); // -> Set R07h: GON = 1, DTE = 0, D[1:0] = 11 config(0x7 , 1 << 5 // GON | 1 << 4 // DTE | 0 << 3 // CM | 3 << 0 // D[1:0] = 3 - operate, display on ); // -> Set R10h at 0000h : Exit sleep mode // R10h [ 00000000 | 0000000 SLP ] // SLP = enter sleep mode (retain but no function) config(0x10, 0); // -> wait 30ms wait(0.030); // -> LCD driver AC setting (R02h) config(0x02, 0x0600); config(0x01, 0x2b3f); // 1011 config(0x25, 0xa000); // 70Hz freq // -> Entry Mode setting (R11h) // R11h [ VSMode DFM1 DFM0 TRANS OEDef WMode DMode1 DMode0 | TY1 TY0 ID1 ID0 AM LG2 LG1 LG0 ] // VSMode = freq dependant on VSYNC // DFM[1:0] colour display mode 11 - 65k, 10 - 262k // TRANS - allow transparent display // OEDef: // When OEDef = 1, OE defines the display window. // When OEDef = 0, the display window is defined by R4Eh and R4Fh. // WMode: Select the source of data to write in the RAM. // 0 Normal data bus (POR) // 1 Generic interface // Dmode - where to show from (0 = ram) // TY - 262k mode options // ID[1:0] [ VERTICAL HORIZONTAL ] increment = 1 decrement = 0 // AM - 0 = horizontal display, 1 = vertical // LG - do maths n written data config(0x11 , 0 << 15 // VSMode | 3 << 13 // DFM[1:0] | 0 << 12 // TRANS | 1 << 11 // OEDef | 0 << 10 // WMode | 0 << 8 // DMode[1:0] | 0 << 6 // TY[1:0] | 3 << 4 // ID[1:0] | 0 << 3 // AM | 0 << 0 // LG[2:0] ); _cs = 1; cls(); } void EA_QVGALCD::pixel(int x, int y, int colour) { window(x, y, 1, 1); putp(colour); } int EA_QVGALCD::width() { return 240; } int EA_QVGALCD::height() { return 320; } void EA_QVGALCD::command(int value) { _spi.write(value & 0xFF); } void EA_QVGALCD::data(int value) { _spi.write(value | 0x100); } void EA_QVGALCD::config(int index, int value) { command(0); command(index); data(value >> 8); data(value); } void EA_QVGALCD::window(int x, int y, int w, int h) { _cs = 0; int hstart = x; int hend = x + w - 1; int vstart = y; int vend = y + h - 1; config(0x44, (hend << 8) | hstart); config(0x45, vstart); config(0x46, vend); config(0x4E, hstart & 0xFF); config(0x4F, vstart & 0x1FF); command(0); command(0x22); _cs = 1; } void EA_QVGALCD::putp(int colour) { _cs = 0; int top = ((colour >> (8+8)) & 0xF8) // r7-3 | ((colour >> (5+8)) & 0x07); // g7-5 int bottom = ((colour >> 5) & 0xE0) // g4-2 | ((colour >> 3) & 0x1F); // b7-3 data(top); data(bottom); _cs = 1; }