Zoltan Hudak / Mbed OS LCD_McuFriend_FSMC_STM32F407

3.5" inch TFT LCD Display Module 480X320 driven with FSMC.

TFT LCD Display Module 480X320 driven with FSMC

I have recently bought a 3.5" inch TFT LCD Touch Screen Display Module 480X320 with a www.mcufriend.com label on the back side. The display was equipped with an 8bit parallel interface. First I decided to test it with the UniGraphic library using the BUS_8 protocol. The display was very slow but improved when I switched to the PAR_8 protocol. Because I heard about the possibility to use a Flexible Static Memory Controller (FSMC), built into some STM MCU's, to drive LCD's (read/write to LCD's memory rather than to an external SRAM) I thought it would be a fun to try it out.

https://os.mbed.com/media/uploads/hudakz/lcd_3.5_tft_480x320_mcufriend_front.png

Below is the brief story of what I did:

  • Selected FSMC in the Connectivity category and configured it as below: https://os.mbed.com/media/uploads/hudakz/arch_max_fsmc_conf.png
  • Let the STM32CubeIDE generate the code (files).
  • Created a new program for the Seeed Arch Max target in the Mbed Online Compiler by selecting a mbed os blinky template.
  • Replaced the main.cpp with the main.c content of the STM32CubeIDE project.
  • Copy & Pasted the other files with codes from the STM32CubeIDE project to the online compiler project.
  • Renamed and modified:
    "stm32f4xx_it.h" to "stm32f4xx_it_msp.h"
    "stm32f4xx_it.c" to "stm32f4xx_it_msp.c"
  • Added the UniGraphic library to the online compiler project.
  • Extended the UniGraphic library with a FSMC_8 protocol and replaced the TFT::set_orientation(int orient) function with the one used by mcufriend for arduino.
  • Modified the main.cpp as needed.
https://os.mbed.com/media/uploads/hudakz/stm32f407vet6_st-link03.pnghttps://os.mbed.com/media/uploads/hudakz/lcd_3.5_tft_480x320_mcufriend_back.png


Wiring

STM32F407VETFT LCD module
+3.3V3V3
GNDGND
PB_12LCD_RST
GNDLCD_CS
PD_13 (RS)LCD_RS
PD_5 (WR)LCD_WR
PD_4 (RD)LCD_RD
PD_14 (DB00)LCD_D0
PD_15 (DB01)LCD_D1
PD_0 (DB02)LCD_D2
PD_1 (DB03)LCD_D3
PE_7 (DB04)LCD_D4
PE_8 (DB05)LCD_D5
PE_9 (DB06)LCD_D6
PE_10 (DB07)LCD_D7



Results
Execution times
Used protocolBUS_8FSMC_8
Operation \ Timemsms
Clear2283.98038.454
Plot192.06611.365
8bit BMP63.80541.338
Large Font163.8727.895
Sparce pixels2072.265/1458.05174.107/52.168
16bit BMP2288.58959.904

UniGraphic/Protocols/SPI16.cpp@1:47c996032a9e, 2020-09-25 (annotated)

Committer:
hudakz
Date:
Fri Sep 25 14:52:27 2020 +0000
Revision:
1:47c996032a9e
Parent:
0:fa952828e34c 
3.5" inch TFT LCD Display Module 480X320 driven with FSMC.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
hudakz 0:fa952828e34c 1 /* mbed UniGraphic library - SPI16 protocol class
hudakz 0:fa952828e34c 2 * Copyright (c) 2015 Giuliano Dianda
hudakz 0:fa952828e34c 3 * Released under the MIT License: http://mbed.org/license/mit
hudakz 0:fa952828e34c 4 *
hudakz 0:fa952828e34c 5 * Derived work of:
hudakz 0:fa952828e34c 6 *
hudakz 0:fa952828e34c 7 * mbed library for 240*320 pixel display TFT based on ILI9341 LCD Controller
hudakz 0:fa952828e34c 8 * Copyright (c) 2013 Peter Drescher - DC2PD
hudakz 0:fa952828e34c 9 *
hudakz 0:fa952828e34c 10 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
hudakz 0:fa952828e34c 11 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
hudakz 0:fa952828e34c 12 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
hudakz 0:fa952828e34c 13 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
hudakz 0:fa952828e34c 14 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
hudakz 0:fa952828e34c 15 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
hudakz 0:fa952828e34c 16 * THE SOFTWARE.
hudakz 0:fa952828e34c 17 */
hudakz 0:fa952828e34c 18
hudakz 0:fa952828e34c 19 #include "SPI16.h"
hudakz 0:fa952828e34c 20
hudakz 0:fa952828e34c 21 SPI16::SPI16(int Hz, PinName mosi, PinName miso, PinName sclk, PinName CS, PinName reset, PinName DC)
hudakz 0:fa952828e34c 22 : _CS(CS), _spi(mosi, miso, sclk), _reset(reset), _DC(DC)
hudakz 0:fa952828e34c 23 {
hudakz 0:fa952828e34c 24 _reset = 1;
hudakz 0:fa952828e34c 25 _DC=1;
hudakz 0:fa952828e34c 26 _CS=1;
hudakz 0:fa952828e34c 27 _spi.format(16,0); // 8 bit spi mode 0
hudakz 0:fa952828e34c 28 // _spi.frequency(12000000); // 10 Mhz SPI clock, 12mhz for F411
hudakz 0:fa952828e34c 29 _spi.frequency(Hz);
hudakz 0:fa952828e34c 30 hw_reset();
hudakz 0:fa952828e34c 31 }
hudakz 0:fa952828e34c 32
hudakz 0:fa952828e34c 33 void SPI16::wr_cmd8(unsigned char cmd)
hudakz 0:fa952828e34c 34 {
hudakz 0:fa952828e34c 35 _spi.format(8,0); // it takes time, better use wr_cmd16 with NOP cmd
hudakz 0:fa952828e34c 36 _DC.write(0); // 0=cmd
hudakz 0:fa952828e34c 37 _spi.write(cmd); // write 8bit
hudakz 0:fa952828e34c 38 _spi.format(16,0);
hudakz 0:fa952828e34c 39 _DC.write(1); // 1=data next
hudakz 0:fa952828e34c 40 }
hudakz 0:fa952828e34c 41 void SPI16::wr_data8(unsigned char data)
hudakz 0:fa952828e34c 42 {
hudakz 0:fa952828e34c 43 _spi.format(8,0); // it takes time, check prev cmd parameter, in case use wr_data16 with repeated byte
hudakz 0:fa952828e34c 44 _spi.write(data); // write 8bit
hudakz 0:fa952828e34c 45 _spi.format(16,0);
hudakz 0:fa952828e34c 46 }
hudakz 0:fa952828e34c 47 void SPI16::wr_cmd16(unsigned short cmd)
hudakz 0:fa952828e34c 48 {
hudakz 0:fa952828e34c 49 _DC.write(0); // 0=cmd
hudakz 0:fa952828e34c 50 _spi.write(cmd); // write 16bit
hudakz 0:fa952828e34c 51 _DC.write(1); // 1=data next
hudakz 0:fa952828e34c 52 }
hudakz 0:fa952828e34c 53 void SPI16::wr_data16(unsigned short data)
hudakz 0:fa952828e34c 54 {
hudakz 0:fa952828e34c 55 _spi.write(data); // write 16bit
hudakz 0:fa952828e34c 56 }
hudakz 0:fa952828e34c 57 void SPI16::wr_gram(unsigned short data)
hudakz 0:fa952828e34c 58 {
hudakz 0:fa952828e34c 59 _spi.write(data); // write 16bit
hudakz 0:fa952828e34c 60 }
hudakz 0:fa952828e34c 61 void SPI16::wr_gram(unsigned short data, unsigned int count)
hudakz 0:fa952828e34c 62 {
hudakz 0:fa952828e34c 63 while(count)
hudakz 0:fa952828e34c 64 {
hudakz 0:fa952828e34c 65 _spi.write(data);
hudakz 0:fa952828e34c 66 count--;
hudakz 0:fa952828e34c 67 }
hudakz 0:fa952828e34c 68 }
hudakz 0:fa952828e34c 69 void SPI16::wr_grambuf(unsigned short* data, unsigned int lenght)
hudakz 0:fa952828e34c 70 {
hudakz 0:fa952828e34c 71 while(lenght)
hudakz 0:fa952828e34c 72 {
hudakz 0:fa952828e34c 73 _spi.write(*data);
hudakz 0:fa952828e34c 74 data++;
hudakz 0:fa952828e34c 75 lenght--;
hudakz 0:fa952828e34c 76 }
hudakz 0:fa952828e34c 77 }
hudakz 0:fa952828e34c 78 unsigned short SPI16::rd_gram(bool convert)
hudakz 0:fa952828e34c 79 {
hudakz 0:fa952828e34c 80 unsigned int r=0;
hudakz 0:fa952828e34c 81 r |= _spi.write(0); // 16bit, whole first byte is dummy, second is red
hudakz 0:fa952828e34c 82 r <<= 16;
hudakz 0:fa952828e34c 83 r |= _spi.write(0);
hudakz 0:fa952828e34c 84 if(convert)
hudakz 0:fa952828e34c 85 {
hudakz 0:fa952828e34c 86 // gram is 18bit/pixel, if you set 16bit/pixel (cmd 3A), during writing the 16bits are expanded to 18bit
hudakz 0:fa952828e34c 87 // during reading, you read the raw 18bit gram
hudakz 0:fa952828e34c 88 r = RGB24to16((r&0xFF0000)>>16, (r&0xFF00)>>8, r&0xFF);// 18bit pixel padded to 24bits, rrrrrr00_gggggg00_bbbbbb00, converted to 16bit
hudakz 0:fa952828e34c 89 }
hudakz 0:fa952828e34c 90 else r >>= 8;
hudakz 0:fa952828e34c 91 _CS = 1; // force CS HIG to interupt the "read state"
hudakz 0:fa952828e34c 92 _CS = 0;
hudakz 0:fa952828e34c 93
hudakz 0:fa952828e34c 94 return (unsigned short)r;
hudakz 0:fa952828e34c 95 }
hudakz 0:fa952828e34c 96 unsigned int SPI16::rd_reg_data32(unsigned char reg)
hudakz 0:fa952828e34c 97 {
hudakz 0:fa952828e34c 98 wr_cmd8(reg);
hudakz 0:fa952828e34c 99 unsigned int r=0;
hudakz 0:fa952828e34c 100
hudakz 0:fa952828e34c 101 r |= _spi.write(0); // we get only 15bit valid, first bit was the dummy cycle
hudakz 0:fa952828e34c 102 r <<= 16;
hudakz 0:fa952828e34c 103 r |= _spi.write(0);
hudakz 0:fa952828e34c 104 r <<= 1; // 32bits are aligned, now collecting bit_0
hudakz 0:fa952828e34c 105 r |= (_spi.write(0) >> 15);
hudakz 0:fa952828e34c 106 // we clocked 15 more bit so ILI waiting for 16th, we need to reset spi bus
hudakz 0:fa952828e34c 107 _CS = 1; // force CS HIG to interupt the cmd
hudakz 0:fa952828e34c 108 _CS = 0;
hudakz 0:fa952828e34c 109 return r;
hudakz 0:fa952828e34c 110 }
hudakz 0:fa952828e34c 111 unsigned int SPI16::rd_extcreg_data32(unsigned char reg, unsigned char SPIreadenablecmd)
hudakz 0:fa952828e34c 112 {
hudakz 0:fa952828e34c 113 unsigned int r=0;
hudakz 0:fa952828e34c 114 for(int regparam=1; regparam<4; regparam++) // when reading EXTC regs, first parameter is always dummy, so start with 1
hudakz 0:fa952828e34c 115 {
hudakz 0:fa952828e34c 116 wr_cmd8(SPIreadenablecmd); // spi-in enable cmd, 0xD9 (ili9341) or 0xFB (ili9488) or don't know
hudakz 0:fa952828e34c 117 wr_data8(0xF0|regparam); // in low nibble specify which reg parameter we want
hudakz 0:fa952828e34c 118 wr_cmd8(reg); // now send cmd (select register we want to read)
hudakz 0:fa952828e34c 119 r <<= 8;
hudakz 0:fa952828e34c 120 r |= (_spi.write(0) >> 8);
hudakz 0:fa952828e34c 121 }
hudakz 0:fa952828e34c 122 _CS = 1; // force CS HIG to interupt the cmd
hudakz 0:fa952828e34c 123 _CS = 0;
hudakz 0:fa952828e34c 124
hudakz 0:fa952828e34c 125 return r;
hudakz 0:fa952828e34c 126 }
hudakz 0:fa952828e34c 127 // ILI932x specific
hudakz 0:fa952828e34c 128 void SPI16::dummyread()
hudakz 0:fa952828e34c 129 {
hudakz 0:fa952828e34c 130 _spi.write(0); // dummy read
hudakz 0:fa952828e34c 131 }
hudakz 0:fa952828e34c 132 // ILI932x specific
hudakz 0:fa952828e34c 133 void SPI16::reg_select(unsigned char reg, bool forread)
hudakz 0:fa952828e34c 134 {
hudakz 0:fa952828e34c 135 _CS = 1; //fixme: really needed?
hudakz 0:fa952828e34c 136 _CS = 0; //fixme: really needed?
hudakz 0:fa952828e34c 137 _spi.write(0x70); // write 0070
hudakz 0:fa952828e34c 138 _spi.write(reg); // write 16bit
hudakz 0:fa952828e34c 139 _CS = 1; //fixme: really needed?
hudakz 0:fa952828e34c 140 _CS = 0; //fixme: really needed?
hudakz 0:fa952828e34c 141 if(forread) _spi.write(0x73);
hudakz 0:fa952828e34c 142 else _spi.write(0x72);
hudakz 0:fa952828e34c 143 }
hudakz 0:fa952828e34c 144 // ILI932x specific
hudakz 0:fa952828e34c 145 void SPI16::reg_write(unsigned char reg, unsigned short data)
hudakz 0:fa952828e34c 146 {
hudakz 0:fa952828e34c 147 _CS = 1; //fixme: really needed?
hudakz 0:fa952828e34c 148 _CS = 0; //fixme: really needed?
hudakz 0:fa952828e34c 149 _spi.write(0x70); // write 0070
hudakz 0:fa952828e34c 150 _spi.write(reg); // write 16bit
hudakz 0:fa952828e34c 151 _CS = 1; //fixme: really needed?
hudakz 0:fa952828e34c 152 _CS = 0; //fixme: really needed?
hudakz 0:fa952828e34c 153 _spi.write(0x72); // write 0072
hudakz 0:fa952828e34c 154 _spi.write(data); // write 16bit
hudakz 0:fa952828e34c 155 }
hudakz 0:fa952828e34c 156 // ILI932x specific
hudakz 0:fa952828e34c 157 unsigned short SPI16::reg_read(unsigned char reg)
hudakz 0:fa952828e34c 158 {
hudakz 0:fa952828e34c 159 unsigned int r=0;
hudakz 0:fa952828e34c 160 _CS = 1; //fixme: really needed?
hudakz 0:fa952828e34c 161 _CS = 0; //fixme: really needed?
hudakz 0:fa952828e34c 162 _spi.write(0x70); // write 0070
hudakz 0:fa952828e34c 163 _spi.write(reg); // write 16bit
hudakz 0:fa952828e34c 164 _CS = 1; //fixme: really needed?
hudakz 0:fa952828e34c 165 _CS = 0; //fixme: really needed?
hudakz 0:fa952828e34c 166 _spi.write(0x73); // write 0073
hudakz 0:fa952828e34c 167 r |= _spi.write(0); // read 16bit, 8bit dummy + 8bit valid
hudakz 0:fa952828e34c 168 r <<= 16;
hudakz 0:fa952828e34c 169 r |= _spi.write(0); // read 16bit
hudakz 0:fa952828e34c 170
hudakz 0:fa952828e34c 171 _CS = 1; //fixme: to resync, maybe really needed
hudakz 0:fa952828e34c 172 _CS = 0; //fixme: to resync, maybe really needed
hudakz 0:fa952828e34c 173 return (r>>8);
hudakz 0:fa952828e34c 174 }
hudakz 0:fa952828e34c 175 void SPI16::hw_reset()
hudakz 0:fa952828e34c 176 {
hudakz 0:fa952828e34c 177 wait_ms(15);
hudakz 0:fa952828e34c 178 _DC = 1;
hudakz 0:fa952828e34c 179 _CS = 1;
hudakz 0:fa952828e34c 180 _reset = 0; // display reset
hudakz 0:fa952828e34c 181 wait_ms(2);
hudakz 0:fa952828e34c 182 _reset = 1; // end reset
hudakz 0:fa952828e34c 183 wait_ms(100);
hudakz 0:fa952828e34c 184 }
hudakz 0:fa952828e34c 185 void SPI16::BusEnable(bool enable)
hudakz 0:fa952828e34c 186 {
hudakz 0:fa952828e34c 187 _CS = enable ? 0:1;
hudakz 0:fa952828e34c 188 }