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#include "clock.h"
#include "delay.h"
#include "gpio.h"
#include "spin.h"
#include "usart.h"
#include "sio.h"
void unhandled_isr_2();
void init();
int in_the_data;
volatile uint32_t delay_amt = 20000000 / 4;
int enable_usart1(uint32_t baud_rate)
{
/* Enable the GPIO bus. */
__IO gpio_port_t* port_b = enable_gpio(GPIO_PORT_B);
/* Enable the USART clock. */
RCC.apb2en_r |= BIT(14);
/* == Configure the IO Pins. == */
/* GPIO D5 (Port B pin 6) is USART1 Tx,
* GPIO D6 (Port B pin 7) is USART1 Rx. */
set_gpio_pin_mode(port_b, PIN_6, MODE_ALTERNATE);
set_gpio_pin_mode(port_b, PIN_7, MODE_ALTERNATE);
/* Set the GPIO pins to use the USART alternate function. */
set_gpio_alternate_function(port_b, PIN_6, AFN_7);
set_gpio_alternate_function(port_b, PIN_7, AFN_7);
RCC.apb2rst_r &= ~BIT(14); /* De-assert reset of USART1 */
uint32_t baud_rate_div = 80000000 / baud_rate;
USART1.c1.r = 0;
USART1.c2.r = 0;
USART1.c3.r = 0;
USART1.br.v = baud_rate_div;
USART1.c1.r |= BIT(3) | BIT(2);
USART1.c1.r |= BIT(0);
/* Enable the transmitter and the receiver. */
usart_set_enabled(&USART1, USART_ENABLE_TX);
asm volatile(" cpsie i ");
}
void dwn() {
int val = 19;
while (val > 1) {
usart_printf(&USART2, "Value: %2d\r\n", val);
if ((val & 1) == 0) {
val /= 2;
} else {
val = val * 3 + 1;
}
}
usart_printf(&USART2, "Value: %2d\r\n", val);
}
/* Main function. This gets executed from the interrupt vector defined above. */
int main()
{
/* Enable the GPIO port B. */
// __IO gpio_port_t* port_b = enable_gpio(GPIO_PORT_B);
// gpio_output_pin_t pin3 = set_gpio_pin_output(port_b, PIN_3);
// gpio_output_pin_t pin1 = set_gpio_pin_output(port_b, PIN_1);
/* Enable a higher clock frequency. */
set_system_clock_MHz(80);
enable_usart2(115200);
int on_the_stack;
USART2.c1.tcie = 1;
USART2.c1.txeie = 1;
// pin_on(pin3);
if (is_usart2_enabled()) {
dwn();
usart_printf(&USART2, "Hello, %d!\r\n", -15);
usart_printf(&USART2, "Hello, %022x\r\n", 0xeadbeef);
usart_printf(&USART2, "on_the_stack: %08X\r\n", (unsigned) &on_the_stack);
int i;
printf("isr-2: %08x\r\n", (unsigned int)(void *) unhandled_isr_2);
printf("init: %08x\r\n", (unsigned int)(void *) init);
for (i = 0; i < 20; ++ i) {
printf("isr %d: %08x\r\n", i, *(unsigned int*)(0x08000000 + i * 4));
}
}
// usart_printf(&USART2, "that_thing: %d\n", *(unsigned*)(0x0));
// for(;;);
}
void do_thing(void(*fn)()) {
fn();
}
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