sdcc-extra/historygraphs/hello-stm8/hello.c

   1 // Source by Philipp Krause under CC0 1.0
   2
   3 // A "Hello, World!"-Program. We use it to make the board
   4 // output something that can not be mistaken for output
   5 // From a benchmark.
   6
   7 #include <stdint.h>
   8 #include <stdio.h>
   9
  10 #define PD_DDR  (*(volatile uint8_t *)0x5011)
  11 #define PD_CR1  (*(volatile uint8_t *)0x5012)
  12
  13 #define CLK_CKDIVR      (*(volatile uint8_t *)0x50c6)
  14 #define CLK_PCKENR1     (*(volatile uint8_t *)0x50c7)
  15
  16 #define USART3_SR       (*(volatile uint8_t *)0x5240)
  17 #define USART3_DR       (*(volatile uint8_t *)0x5241)
  18 #define USART3_BRR1     (*(volatile uint8_t *)0x5242)
  19 #define USART3_BRR2     (*(volatile uint8_t *)0x5243)
  20 #define USART3_CR2      (*(volatile uint8_t *)0x5245)
  21 #define USART3_CR3      (*(volatile uint8_t *)0x5246)
  22
  23 #define USART_CR2_TEN (1 << 3)
  24 #define USART_CR3_STOP2 (1 << 5)
  25 #define USART_CR3_STOP1 (1 << 4)
  26 #define USART_SR_TXE (1 << 7)
  27
  28 #if defined(__CSMC__) // Cosmic weirdness
  29 char putchar(char c)
  30 {
  31         while(!(USART3_SR & USART_SR_TXE));
  32
  33         USART3_DR = c;
  34
  35         return c;
  36 }
  37 #elif defined(__RCSTM8__) // Raisonance weirdness
  38 int putchar(char c)
  39 {
  40         while(!(USART3_SR & USART_SR_TXE));
  41
  42         USART3_DR = c;
  43
  44         return(c);
  45 }
  46 #elif defined(__SDCC) && __SDCC_REVISION < 9624 // Old SDCC weirdness
  47 void putchar(char c)
  48 {
  49         while(!(USART3_SR & USART_SR_TXE));
  50
  51         USART3_DR = c;
  52 }
  53 #else // Standard C
  54 int putchar(int c)
  55 {
  56         while(!(USART3_SR & USART_SR_TXE));
  57
  58         USART3_DR = c;
  59
  60         return(c);
  61 }
  62 #endif
  63
  64 void main(void)
  65 {
  66         unsigned long i = 0;
  67
  68         CLK_CKDIVR = 0x00; // Set the frequency to 16 MHz
  69         CLK_PCKENR1 = 0xFF; // Enable peripherals
  70
  71         PD_DDR = 0x20; // Put TX line on
  72         PD_CR1 = 0x20;
  73
  74         USART3_CR2 = USART_CR2_TEN; // Allow TX and RX
  75         USART3_CR3 &= ~(USART_CR3_STOP1 | USART_CR3_STOP2); // 1 stop bit
  76         USART3_BRR2 = 0x03; USART3_BRR1 = 0x68; // 9600 baud
  77
  78         for(;;)
  79         {
  80                 printf("Hello, World!\n");
  81                 for(i = 0; i < 147456; i++); // Sleep
  82         }
  83 }
  84