LCD on STMf4xx using FSMC

Shane Gingell · ‎2018-07-09

Posted on July 09, 2018 at 09:04

I have been teaching myself to user the STM32 MCUs.

I have done the usual blink and LED and create a Delay timer, setup a UART as a serial console for debugging.

I did also write a I2C software slave using and interrupt on the SDA line to detect the master sending a start condition.

I am now tring to use a LCD TFT in parallel using FSMC. I have tried both a ST7781 in 8 bit parallel and now a HX8357 in 16 bit parallel.

The FSCM seems to be working correctly as if I out my scope on any of the pins I see the output that I would expect but nothign shows up on the screen.

here's my code

#include 'stm32f4xx.h'

//used for coutn down in Delay

__IO uint32_t TimmingDelay;

void SysTick_Handler(void)

{

if(TimmingDelay !=0)

{

TimmingDelay --;

}

void Delay(__IO uint32_t time)

{

TimmingDelay = time;

while(TimmingDelay !=0);

}

//pointer used to write to start address of FSMC

volatile uint16_t* fsmc = (uint16_t*)0x60000000;

void FSMC_setup(void){

//enable RCC for FSMC and both GPIO ports

RCC->AHB3ENR |= RCC_AHB3ENR_FSMCEN;

RCC->AHB1ENR |= RCC_AHB1ENR_GPIODEN | RCC_AHB1ENR_GPIOEEN;

//setup RS (PD13) and RST (PD12) pin as output

GPIOD->MODER |= GPIO_MODER_MODER13_0 | GPIO_MODER_MODER12_0;

//setup other pins as AF

//setup pins as PP

GPIOD->OTYPER = 0x00000000;

GPIOE->OTYPER = 0x00000000;

//set speed to 100MHz

GPIOD->OSPEEDR = 0xFFFFFFFF;

GPIOE->OSPEEDR = 0xFFFFFFFF;

//set NO pull-up or pull-down

GPIOD->PUPDR = 0x00000000;

GPIOE->PUPDR = 0x00000000;

//set other pins to AF12 i.e as FSMC pins

GPIOE->AFR[0] |= (GPIO_AF12_FSMC << (7 * 4));

//setup FSMC on Bank1 NORSRAM1

//disable ASYNCWAIT:

FSMC_Bank1->BTCR[0] &= ~FSMC_BCR1_ASYNCWAIT;

//disable Extended mode

FSMC_Bank1->BTCR[0] &= ~FSMC_BCR1_EXTMOD;

//disable the wait for NWAIT signal

FSMC_Bank1->BTCR[0] &= ~FSMC_BCR1_WAITEN;

//write enable

FSMC_Bank1->BTCR[0] |= FSMC_BCR1_WREN;

//disable wrap mode

FSMC_Bank1->BTCR[0] &= ~FSMC_BCR1_WRAPMOD;

//disable Burst mode

FSMC_Bank1->BTCR[0] &= ~FSMC_BCR1_BURSTEN;

//enable Flash access

FSMC_Bank1->BTCR[0] |= FSMC_BCR1_FACCEN;

//set data bus width to 16 bit

FSMC_Bank1->BTCR[0] |= FSMC_BCR1_MWID_0;

//set to SRAM type

FSMC_Bank1->BTCR[0] &= ~FSMC_BCR1_MTYP;

//disable Address/data multiplexing

FSMC_Bank1->BTCR[0] &= ~FSMC_BCR1_MUXEN;

//enable Memory bank

FSMC_Bank1->BTCR[0] |= FSMC_BCR1_MBKEN;

//setup timings

//set access mode A

FSMC_Bank1->BTCR[1] &= ~FSMC_BTR1_ACCMOD;

//set short bus turn around

FSMC_Bank1->BTCR[1] &= ~(FSMC_BTR1_BUSTURN_0 | FSMC_BTR1_BUSTURN_1 | FSMC_BTR1_BUSTURN_2 |FSMC_BTR1_BUSTURN_3);

}

void TFT_write_cmd(uint16_t command){

//set RS pin low

GPIOD->ODR &= ~GPIO_ODR_ODR_13;

Delay(10);

*fsmc = command;

//set RS pin high

GPIOD->ODR |= GPIO_ODR_ODR_13;

Delay(10);

}

//sets up a HX8357B TFT

void TFT_setup(void){

//hardware reset

GPIOD->ODR &= ~GPIO_ODR_ODR_12;

Delay(200);

GPIOD->ODR |= GPIO_ODR_ODR_12;

Delay(120);

//software reset

TFT_write_cmd(0x01);

Delay(120);

//sleep out

TFT_write_cmd(0x11);

Delay(120);

//Normal Display Mode On)

TFT_write_cmd(0x13);

//Display On

TFT_write_cmd(0x29);

//CASET (Column Address Set)

TFT_write_cmd(0x2A);

*fsmc = 0000;

*fsmc = 320;

//PASET (Page Address Set)

TFT_write_cmd(0x2B);

*fsmc = 0000;

*fsmc = 320;

//Exit_idle_mode

TFT_write_cmd(0x38);

//Set_pixel_format RGR565 16 bit

TFT_write_cmd(0x3A);

*fsmc = 0b01010101;

//RAMWR (Memory Write)

TFT_write_cmd(0x2C);

}

void main(void){

// At this stage the system clock should have already been configured

// at high speed.

//set systick for 1 MS used in Delay interrupt

SysTick_Config(SystemCoreClock/1000);

FSMC_setup();

TFT_setup();

for (uint32_t i = 0; i < 102400; ++i ){

*fsmc = 0xff00;

fsmc += 2;

}

// Infinite loop

while (1){

// Add your code here.

}

Shane Gingell · ‎2018-07-12

Posted on July 12, 2018 at 11:42

I have found solution to my setup FSMC problem.

Here is working setup

//setup timings of FSCM

FSMC_Bank1->BTCR[1] = FSMC_BTR1_ADDSET_1 | FSMC_BTR1_DATAST_1;

// Bank1 NOR/SRAM control register configuration

FSMC_Bank1->BTCR[0] = FSMC_BCR1_MWID_0 | FSMC_BCR1_WREN | FSMC_BCR1_MBKEN;