From 6af143dd8f5f61bafcefbdfdc3ae0b64841cc5da Mon Sep 17 00:00:00 2001
From: jaseg <git@jaseg.de>
Date: Wed, 23 Aug 2023 19:24:25 +0200
Subject: [PATCH] Timer experiments WIP

---
 include/global.h |  1 +
 src/main.c       | 30 +++++++++++++++++++++++++-----
 2 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/include/global.h b/include/global.h
index d3fa85e..6a11324 100644
--- a/include/global.h
+++ b/include/global.h
@@ -25,6 +25,7 @@
 #define CLEAR(pin) (~(3<<(2*(pin))))
 #define PULLUP(pin) (1<<(2*pin))
 #define PULLDOWN(pin) (2<<(2*pin))
+#define OSPEED(pin, val) ((val) << ((pin)*2))
 #define BSRR_CLEAR(pin) ((1<<pin)<<16)
 #define BSRR_SET(pin) (1<<pin)
 #define BSRR_VALUE(pin, value) ((((!(value))<<pin)<<16) | ((!!(value))<<pin))
diff --git a/src/main.c b/src/main.c
index 0038768..62869e0 100644
--- a/src/main.c
+++ b/src/main.c
@@ -11,7 +11,6 @@ int main(void) {
      * HSE @ 8 MHz --[PLL x42 /2]--> PLL "R" clock @ 168 MHz
      */
     /* Enable peripherals */
-    RCC->AHB2ENR |= RCC_AHB2ENR_GPIOAEN;
     RCC->APB1ENR1 |= RCC_APB1ENR1_PWREN;
     /* Enable High-speed external crystal oscillator. The board has an 8 MHz crystal. */
     RCC->CR |= RCC_CR_HSEON;
@@ -37,16 +36,37 @@ int main(void) {
         /* wait for RCC to switch over. */
     }
 
+    RCC->AHB2ENR |= RCC_AHB2ENR_GPIOAEN | RCC_AHB2ENR_GPIOBEN;
+    RCC->APB2ENR |= RCC_APB2ENR_TIM1EN;
+    GPIOA->MODER &= CLEAR(8) & CLEAR(9);
+    GPIOA->MODER |= AF(8) | AF(9);
+    GPIOA->AFR[1] |= AFRH(8, 6) | AFRH(9, 6);
+    GPIOA->OSPEEDR |= OSPEED(8, 3) | OSPEED(9, 3);
+    GPIOB->MODER &= CLEAR(13) & CLEAR(14);
+    GPIOB->MODER |= AF(13) | AF(14);
+    GPIOB->AFR[1] |= AFRH(13, 6) | AFRH(14, 6);
+    GPIOB->OSPEEDR |= OSPEED(13, 3) | OSPEED(14, 3);
+    TIM1->CCMR1 = (6<<TIM_CCMR1_OC1M_Pos) | (7<<TIM_CCMR1_OC2M_Pos);
+    TIM1->CCER = TIM_CCER_CC1E | TIM_CCER_CC1NE | TIM_CCER_CC2E | TIM_CCER_CC2NE;
+    TIM1->PSC = 0;
+    TIM1->ARR = 168*3;
+    TIM1->CCR1 = TIM1->ARR/2;
+    TIM1->CCR2 = TIM1->ARR/2;
+    TIM1->BDTR = TIM_BDTR_MOE | (64<<TIM_BDTR_DTG_Pos);
+    TIM1->CR1 = TIM_CR1_CEN;
+
+    //GPIOA->MODER |= OUT(8) | OUT(9);
+    //GPIOB->MODER |= OUT(13) | OUT(14);
+
     GPIOA->MODER &= CLEAR(5) & CLEAR(6) & CLEAR(7);
     GPIOA->MODER |= OUT(5) | OUT(6) | OUT(7); /* Status LEDs */
+    GPIOA->BSRR = (1<<6);
 
     int j = 0;
     while(23) {
         j++;
-        if (j == 3)
-            j = 0;
-        GPIOA->BSRR = (((1<<5) | (1<<6) | (1<<7)) << 16) | ((~((1<<5) << j))&((1<<5)|(1<<6)|(1<<7)));
-        for(int i=0; i<5000000; i++) {
+        GPIOA->BSRR = ((j&1)<<5) | ((1<<5)<<16);
+        for(int i=0; i<2000000; i++) {
             asm volatile ("nop");
         }
     }