#include "stm8s.h"

//

// Setup the system clock to run at 16MHz using the internal oscillator.

//

void InitialiseSystemClock()

{

CLK_ICKR = 0; // Reset the Internal Clock Register.

CLK_ICKR = CLK_ICKR_HSIEN; // Enable the HSI.

CLK_ECKR = 0; // Disable the external clock.

while (!(CLK_ICKR & CLK_ICKR_HSIRDY)); // Wait for the HSI to be ready for use.

CLK_CKDIVR = 0; // Ensure the clocks are running at full speed.

CLK_PCKENR1 = 0xff; // Enable all peripheral clocks.

CLK_PCKENR2 = 0xff; // Ditto.

CLK_CCOR = 0; // Turn off CCO.

CLK_HSITRIMR = 0; // Turn off any HSIU trimming.

CLK_SWIMCCR = 0; // Set SWIM to run at clock / 2.

CLK_SWR = 0xe1; // Use HSI as the clock source.

CLK_SWCR = 0; // Reset the clock switch control register.

CLK_SWCR = CLK_SWCR_SWEN; // Enable switching.

while (CLK_SWCR & CLK_SWCR_SWBSY); // Pause while the clock switch is busy.

}

//

// Setup the USART to run at 115200 baud, no parity, one stop bit, 8 data bits.

//

// Important: This relies upon the system clock being set to run at 16 MHz.

//

void InitialiseUSART()

{

//

// Clear the Idle Line Detected bit in the status register by a read

// to the USART1_SR register followed by a Read to the USART1_DR register.

//

unsigned char tmp = USART1_SR;

tmp = USART1_DR;

//

// Reset the USART registers to the reset values.

//

USART1_CR1 = 0;

USART1_CR2 = 0;

USART1_CR4 = 0;

USART1_CR3 = 0;

USART1_CR5 = 0;

USART1_GTR = 0;

USART1_PSCR = 0;

//

// Now setup the port to 115200,n,8,1.

//

USART1_CR1 &= ~USART_CR1_M; // 8 Data bits.

USART1_CR1 &= ~USART_CR1_PCEN; // Disable parity.

USART1_CR3 &= ~(USART_CR3_STOP1|USART_CR3_STOP2) ; // 1 stop bit.

USART1_BRR2 = 0x0b; // Set the baud rate registers to 115200 baud

USART1_BRR1 = 0x08; // based upon a 16 MHz system clock.

//

// Disable the transmitter and receiver.

//

USART1_CR2 &= ~(USART_CR2_TEN|USART_CR2_REN);

//

// Set the clock polarity and lock phase.

//

USART1_CR3 = (USART_CR3_CPOL|USART_CR3_CPHA);

//

// Turn on the USART transmit and receive.

//

USART1_CR2 |= (USART_CR2_TEN|USART_CR2_REN);

}

//

// Send a message to the debug port (USART1).

//

void USARTPrintf(char *message)

{

char *ch = message;

while (*ch)

{

USART1_DR = (unsigned char) *ch; // Put the next character into the data transmission register.

while (!(USART1_SR & USART_SR_TXE)); // Wait for transmission to complete.

ch++; // Grab the next character.

}

}

//

// Main program loop.

//

int main(void)

{

int d;

__disable_interrupt();

InitialiseSystemClock();

InitialiseUSART();

__enable_interrupt();

// Configure pins

PD_DDR = 0x01;

PD_CR1 = 0x01;

// Loop

do {

PD_ODR ^= 0x01;

for(d = 0; d < 29000; d++) { }

USARTPrintf("Hello from my microcontroller....\n\r");

} while(1);

}