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/FSMC8.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 #include "FSMC8.h"
hudakz 0:fa952828e34c 2 #include "stdint.h"
hudakz 0:fa952828e34c 3
hudakz 0:fa952828e34c 4 // Addres bit A18 is used to select LCD's REGISTER or RAM: A18 = 0b00000000000001000000000000000000 = 0x00040000
hudakz 0:fa952828e34c 5 volatile unsigned char* lcd_reg = (unsigned char*)0x60000000; // FSMC BANK1, A18 = 0 -> write to LCD's REGISTER
hudakz 0:fa952828e34c 6 volatile unsigned char* lcd_ram = (unsigned char*)0x60040000; // FSMC BANK1, A18 = 1 -> read/write to LCD's RAM
hudakz 0:fa952828e34c 7
hudakz 0:fa952828e34c 8 /**
hudakz 0:fa952828e34c 9 * @brief
hudakz 0:fa952828e34c 10 * @note
hudakz 0:fa952828e34c 11 * @param
hudakz 0:fa952828e34c 12 * @retval
hudakz 0:fa952828e34c 13 */
hudakz 0:fa952828e34c 14 FSMC8::FSMC8(PinName reset) :
hudakz 0:fa952828e34c 15 _reset(reset)
hudakz 0:fa952828e34c 16 {
hudakz 0:fa952828e34c 17 _reset = 1;
hudakz 0:fa952828e34c 18 }
hudakz 0:fa952828e34c 19
hudakz 0:fa952828e34c 20
hudakz 0:fa952828e34c 21 /**
hudakz 0:fa952828e34c 22 * @brief
hudakz 0:fa952828e34c 23 * @note
hudakz 0:fa952828e34c 24 * @param
hudakz 0:fa952828e34c 25 * @retval
hudakz 0:fa952828e34c 26 */
hudakz 0:fa952828e34c 27 void FSMC8::wr_cmd8(unsigned char cmd)
hudakz 0:fa952828e34c 28 {
hudakz 0:fa952828e34c 29 lcd_reg[0] = cmd; // Write to LCD's register
hudakz 0:fa952828e34c 30 }
hudakz 0:fa952828e34c 31
hudakz 0:fa952828e34c 32 /**
hudakz 0:fa952828e34c 33 * @brief
hudakz 0:fa952828e34c 34 * @note
hudakz 0:fa952828e34c 35 * @param
hudakz 0:fa952828e34c 36 * @retval
hudakz 0:fa952828e34c 37 */
hudakz 0:fa952828e34c 38 void FSMC8::wr_data8(unsigned char data)
hudakz 0:fa952828e34c 39 {
hudakz 0:fa952828e34c 40 lcd_ram[0] = data; // Write to LCD's RAM
hudakz 0:fa952828e34c 41 }
hudakz 0:fa952828e34c 42
hudakz 0:fa952828e34c 43 /**
hudakz 0:fa952828e34c 44 * @brief
hudakz 0:fa952828e34c 45 * @note
hudakz 0:fa952828e34c 46 * @param
hudakz 0:fa952828e34c 47 * @retval
hudakz 0:fa952828e34c 48 */
hudakz 0:fa952828e34c 49 void FSMC8::wr_cmd16(unsigned short cmd)
hudakz 0:fa952828e34c 50 {
hudakz 0:fa952828e34c 51 wr_cmd8(cmd >> 8); // Write MSB to LCD's register
hudakz 0:fa952828e34c 52 wr_cmd8(cmd & 0xFF); // Write LSB to LCD's register
hudakz 0:fa952828e34c 53 }
hudakz 0:fa952828e34c 54
hudakz 0:fa952828e34c 55 /**
hudakz 0:fa952828e34c 56 * @brief
hudakz 0:fa952828e34c 57 * @note
hudakz 0:fa952828e34c 58 * @param
hudakz 0:fa952828e34c 59 * @retval
hudakz 0:fa952828e34c 60 */
hudakz 0:fa952828e34c 61 void FSMC8::wr_data16(unsigned short data)
hudakz 0:fa952828e34c 62 {
hudakz 0:fa952828e34c 63 wr_data8(data >> 8); // Write MSB to LCD's RAM
hudakz 0:fa952828e34c 64 wr_data8(data & 0xFF); // Write LSB to LCD's RAM
hudakz 0:fa952828e34c 65
hudakz 0:fa952828e34c 66 }
hudakz 0:fa952828e34c 67
hudakz 0:fa952828e34c 68 /**
hudakz 0:fa952828e34c 69 * @brief
hudakz 0:fa952828e34c 70 * @note
hudakz 0:fa952828e34c 71 * @param
hudakz 0:fa952828e34c 72 * @retval
hudakz 0:fa952828e34c 73 */
hudakz 0:fa952828e34c 74 void FSMC8::wr_gram(unsigned short data)
hudakz 0:fa952828e34c 75 {
hudakz 0:fa952828e34c 76 wr_data16(data);
hudakz 0:fa952828e34c 77 }
hudakz 0:fa952828e34c 78
hudakz 0:fa952828e34c 79 /**
hudakz 0:fa952828e34c 80 * @brief
hudakz 0:fa952828e34c 81 * @note
hudakz 0:fa952828e34c 82 * @param
hudakz 0:fa952828e34c 83 * @retval
hudakz 0:fa952828e34c 84 */
hudakz 0:fa952828e34c 85 void FSMC8::wr_gram(unsigned short data, unsigned int count)
hudakz 0:fa952828e34c 86 {
hudakz 0:fa952828e34c 87 if ((data >> 8) == (data & 0xFF)) {
hudakz 0:fa952828e34c 88 count <<= 1;
hudakz 0:fa952828e34c 89 while (count) {
hudakz 0:fa952828e34c 90 wr_data8(data);
hudakz 0:fa952828e34c 91 count--;
hudakz 0:fa952828e34c 92 }
hudakz 0:fa952828e34c 93 }
hudakz 0:fa952828e34c 94 else {
hudakz 0:fa952828e34c 95 while (count) {
hudakz 0:fa952828e34c 96 wr_data16(data);
hudakz 0:fa952828e34c 97 count--;
hudakz 0:fa952828e34c 98 }
hudakz 0:fa952828e34c 99 }
hudakz 0:fa952828e34c 100 }
hudakz 0:fa952828e34c 101
hudakz 0:fa952828e34c 102 /**
hudakz 0:fa952828e34c 103 * @brief
hudakz 0:fa952828e34c 104 * @note
hudakz 0:fa952828e34c 105 * @param
hudakz 0:fa952828e34c 106 * @retval
hudakz 0:fa952828e34c 107 */
hudakz 0:fa952828e34c 108 void FSMC8::wr_grambuf(unsigned short* data, unsigned int lenght)
hudakz 0:fa952828e34c 109 {
hudakz 0:fa952828e34c 110 while (lenght) {
hudakz 0:fa952828e34c 111 wr_data16(*data++);
hudakz 0:fa952828e34c 112 lenght--;
hudakz 0:fa952828e34c 113 }
hudakz 0:fa952828e34c 114 }
hudakz 0:fa952828e34c 115
hudakz 0:fa952828e34c 116 /**
hudakz 0:fa952828e34c 117 * @brief
hudakz 0:fa952828e34c 118 * @note
hudakz 0:fa952828e34c 119 * @param
hudakz 0:fa952828e34c 120 * @retval
hudakz 0:fa952828e34c 121 */
hudakz 0:fa952828e34c 122 unsigned char FSMC8::rd_data8(unsigned int i /* = 0 */)
hudakz 0:fa952828e34c 123 {
hudakz 0:fa952828e34c 124 return lcd_ram[i]; // Read from LCD's RAM
hudakz 0:fa952828e34c 125 }
hudakz 0:fa952828e34c 126
hudakz 0:fa952828e34c 127 /**
hudakz 0:fa952828e34c 128 * @brief
hudakz 0:fa952828e34c 129 * @note
hudakz 0:fa952828e34c 130 * @param
hudakz 0:fa952828e34c 131 * @retval
hudakz 0:fa952828e34c 132 */
hudakz 0:fa952828e34c 133 unsigned short FSMC8::rd_gram(bool convert)
hudakz 0:fa952828e34c 134 {
hudakz 0:fa952828e34c 135 unsigned int r = 0;
hudakz 0:fa952828e34c 136
hudakz 0:fa952828e34c 137 rd_data8(); // dummy read
hudakz 0:fa952828e34c 138 r |= rd_data8();
hudakz 0:fa952828e34c 139 r <<= 8;
hudakz 0:fa952828e34c 140 r |= rd_data8();
hudakz 0:fa952828e34c 141
hudakz 0:fa952828e34c 142 if (convert) {
hudakz 0:fa952828e34c 143 r <<= 8;
hudakz 0:fa952828e34c 144 r |= rd_data8();
hudakz 0:fa952828e34c 145
hudakz 0:fa952828e34c 146 // gram is 18bit/pixel, if you set 16bit/pixel (cmd 3A), during writing the 16bits are expanded to 18bit
hudakz 0:fa952828e34c 147 // during reading, you read the raw 18bit gram
hudakz 0:fa952828e34c 148 r = RGB24to16((r & 0xFF0000) >> 16, (r & 0xFF00) >> 8, r & 0xFF); // 18bit pixel padded to 24bits, rrrrrr00_gggggg00_bbbbbb00, converted to 16bit
hudakz 0:fa952828e34c 149 }
hudakz 0:fa952828e34c 150
hudakz 0:fa952828e34c 151 // _bus.output();
hudakz 0:fa952828e34c 152 return (unsigned short)r;
hudakz 0:fa952828e34c 153 }
hudakz 0:fa952828e34c 154
hudakz 0:fa952828e34c 155 /**
hudakz 0:fa952828e34c 156 * @brief
hudakz 0:fa952828e34c 157 * @note
hudakz 0:fa952828e34c 158 * @param
hudakz 0:fa952828e34c 159 * @retval
hudakz 0:fa952828e34c 160 */
hudakz 0:fa952828e34c 161 unsigned int FSMC8::rd_reg_data32(unsigned char reg)
hudakz 0:fa952828e34c 162 {
hudakz 0:fa952828e34c 163 unsigned char data[4] = { 0 };
hudakz 0:fa952828e34c 164 unsigned int* r = (unsigned int*)&data[0];
hudakz 0:fa952828e34c 165
hudakz 0:fa952828e34c 166 wr_cmd8(reg);
hudakz 0:fa952828e34c 167 data[3] = rd_data8(0);
hudakz 0:fa952828e34c 168 data[2] = rd_data8(0);
hudakz 0:fa952828e34c 169 data[1] = rd_data8(0);
hudakz 0:fa952828e34c 170 data[0] = rd_data8(0);
hudakz 0:fa952828e34c 171
hudakz 0:fa952828e34c 172 return *r;
hudakz 0:fa952828e34c 173 }
hudakz 0:fa952828e34c 174
hudakz 0:fa952828e34c 175 // in Par mode EXTC regs (0xB0-0xFF) can be directly read
hudakz 0:fa952828e34c 176 unsigned int FSMC8::rd_extcreg_data32(unsigned char reg, unsigned char SPIreadenablecmd)
hudakz 0:fa952828e34c 177 {
hudakz 0:fa952828e34c 178 return rd_reg_data32(reg);
hudakz 0:fa952828e34c 179 }
hudakz 0:fa952828e34c 180
hudakz 0:fa952828e34c 181 // ILI932x specific
hudakz 0:fa952828e34c 182 void FSMC8::dummyread()
hudakz 0:fa952828e34c 183 {
hudakz 0:fa952828e34c 184 rd_data8(); // dummy read
hudakz 0:fa952828e34c 185 }
hudakz 0:fa952828e34c 186
hudakz 0:fa952828e34c 187 // ILI932x specific
hudakz 0:fa952828e34c 188 void FSMC8::reg_select(unsigned char reg, bool forread)
hudakz 0:fa952828e34c 189 {
hudakz 0:fa952828e34c 190 wr_cmd8(0); // write MSB
hudakz 0:fa952828e34c 191 wr_cmd8(reg); // write LSB
hudakz 0:fa952828e34c 192 }
hudakz 0:fa952828e34c 193
hudakz 0:fa952828e34c 194 // ILI932x specific
hudakz 0:fa952828e34c 195 void FSMC8::reg_write(unsigned char reg, unsigned short data)
hudakz 0:fa952828e34c 196 {
hudakz 0:fa952828e34c 197 wr_cmd8(0); // write MSB
hudakz 0:fa952828e34c 198 wr_cmd8(reg); // write LSB
hudakz 0:fa952828e34c 199 wr_data16(data);
hudakz 0:fa952828e34c 200 }
hudakz 0:fa952828e34c 201
hudakz 0:fa952828e34c 202 // ILI932x specific
hudakz 0:fa952828e34c 203 unsigned short FSMC8::reg_read(unsigned char reg)
hudakz 0:fa952828e34c 204 {
hudakz 0:fa952828e34c 205 unsigned short r = 0;
hudakz 0:fa952828e34c 206
hudakz 0:fa952828e34c 207 wr_cmd8(0);
hudakz 0:fa952828e34c 208 wr_cmd8(reg);
hudakz 0:fa952828e34c 209 r |= rd_data8() & 0xFF;
hudakz 0:fa952828e34c 210 r <<= 8;
hudakz 0:fa952828e34c 211 r |= rd_data8() & 0xFF;
hudakz 0:fa952828e34c 212
hudakz 0:fa952828e34c 213 return r;
hudakz 0:fa952828e34c 214 }
hudakz 0:fa952828e34c 215
hudakz 0:fa952828e34c 216 /**
hudakz 0:fa952828e34c 217 * @brief
hudakz 0:fa952828e34c 218 * @note
hudakz 0:fa952828e34c 219 * @param
hudakz 0:fa952828e34c 220 * @retval
hudakz 0:fa952828e34c 221 */
hudakz 0:fa952828e34c 222 void FSMC8::hw_reset()
hudakz 0:fa952828e34c 223 {
hudakz 0:fa952828e34c 224 _reset = 1;
hudakz 0:fa952828e34c 225 wait_ms(15);
hudakz 0:fa952828e34c 226 _reset = 0; // display reset
hudakz 0:fa952828e34c 227 wait_ms(2);
hudakz 0:fa952828e34c 228 _reset = 1; // end reset
hudakz 0:fa952828e34c 229 wait_ms(100);
hudakz 0:fa952828e34c 230 }