TIMER doesnt work when i link the lcd

[LFerr.7]

#define TRIAC_PULSE_WIDTH  500  // Duration of TRIAC trigger pulse in µs
 
lcd_init();
 
  lcd_send_cmd (0x80|0x00);
  lcd_send_string("HELLO WORLD");
 
  lcd_send_cmd (0x80|0x40);
  lcd_send_string("LCD 20x4 DEMO");
 
  lcd_send_cmd (0x80|0x1C);
  lcd_send_string("BY");
 
  lcd_send_cmd (0x80|0x54);
    lcd_send_string("powertechnologies");
 
void timer1_init( void )
{
   __HAL_RCC_TIM1_CLK_ENABLE(); // Enable Timer 1 clock
   TIM1->CR1   = 0x0088;        // Auto-reload, One-Pulse-Mode 
   TIM1->CR2   = 0x0000;        // Idle-state configuration
   TIM1->SMCR  = 0x0066;        // Trigger-Mode, Timer input 2
   TIM1->DIER  = 0x0000;        // Disable interrupts
   TIM1->SR    = 0x0000;        // Clear status register
   TIM1->EGR   = 0x0000;        // Clear event generation register
   TIM1->CCMR1 = 0x0178;        // OC1: PWM2-Mode, Preload, IC2: IC2 on TI2
   TIM1->CCMR2 = 0x0000;        // OC3/OC4, IC3/IC4 off
   TIM1->CCER  = 0x00A1;        // OC1: On, AH; IC2: On, Both edges  
   TIM1->CNT   = 0;             // Clear timer 1 counter
   TIM1->PSC   = 168-1;         // Set prescaler to 168
   TIM1->ARR   = 0x0000;        // Initialize Auto-reload register
   TIM1->RCR   = 0x0000;        // Clear repetition counter     
   TIM1->CCR1  = 0x0000;        // Initialize Capture/Compare register 1
   TIM1->CCR2  = 0x0000;        // Clear Capture/Compare register 2
   TIM1->CCR3  = 0x0000;        // Clear Capture/Compare register 3
   TIM1->CCR4  = 0x0000;        // Clear Capture/Compare register 4
   TIM1->BDTR  = 0x8000;        // Main output enable
   TIM1->DCR   = 0x0000;        // Clear DMA configuration (DMA not needed)
   // TIM1->DMAR = ......;      
   TIM1->CR1  |= 0x0001;        // Timer 1 Enable
}
 
void gpio_init( void )
{
   __HAL_RCC_GPIOE_CLK_ENABLE();    // Enable GPIOE clock
   GPIOE->MODER   = 0x00880000;     // Enable PE9/PE11 alternate function mode
   GPIOE->AFR[1]  = 0x00001010;     // Select PE9/PE11 alternate function AF1
   GPIOE->AFR[0]  = 0x00000000;     // Clear AFRL
   GPIOE->OTYPER  = 0x00000000;     // Set all outputs to push-pull mode (default)
   GPIOE->OSPEEDR = 0x00000000;     // Set all outputs to low-speed (default)
   GPIOE->PUPDR   = 0x00000000;     // Disable all pull-ups and pull-downs
}
 
 
void set_alpha( int alpha )
{
   TIM1->CCR1 = alpha;
   TIM1->ARR = alpha + TRIAC_PULSE_WIDTH;     
}

I use STM32F429ZI and stmcube ide to write the code. I have activate the timer 1 (ch1 at output compare PE9 and ch2 input capture PE11 ).

On PE11 i put a quare wave of 50 hz and in the output(PE9 i have the pulses every rising and falling edges.)The lcd works very fine (i2c but i have tried also spi and it works.) but when i connect the lcd to send strings(for example when i write lcd init(), the timer output(PE9 ) go up at 3.3v and the pulse misses.

Can you help me please? if you want more information , i can be more clear.

[waclawek.jan]

> for example when i write lcd init(), the timer output(PE9 ) go up at 3.3v and the pulse misses

Read out and check/compare GPIOE and timer registers content between working and non-working cases.

JW

[LFerr.7]

thanks for your answer, i have tried a lot , reading manual , changing things on code but without result.

[waclawek.jan]

That's why I say, read out the content of registers and check/compare/post.

JW

[Andrew Neil]

@LFerr.7​  "The lcd works very fine (i2c but i have tried also spi and it works.) but when i connect the lcd to send strings(for example when i write lcd init(), the timer output(PE9 ) go up at 3.3v and the pulse misses."

Not quite clear what you're saying here - is this purely a software change, or are you also changing hardware?

As @Community member​ says, whenever you have one working and one non-working case, the thing to do is to compare them side-by-side - step through, and see where things are different.

Or, perhaps, go back to the working case and just make small, incremental changes - so you don't have much to debug at the point that it stops working...

[LFerr.7]

It is a software change. I see on the oscilloscope that in the output of timer i have Constant voltage 3,3V instead of the pulses

[Tesla DeLorean]

Blind writing all the pin configuration,etc, looks like it will cause headaches and waste time.

Think harder, and tread more carefully..

[LFerr.7]

thank you

[Andrew Neil]

so compare & contrast your timer setup in the 2 cases