some i/o fixes

aaio.h

@@ -152,7 +152,7 @@ void aaio_led_toggle() {
 }
 
 /* set the internal LED */
-void aaio_led_set(uint8_t v) {
+void aaio_led_set(register uint8_t v) {
   if(v == 0) {
     AAIO_LED_PORT &= ~(1 << AAIO_LED_PIN);
   } else {
@@ -182,7 +182,7 @@ void aaio_uart_init(void) {
 }
 
 /* put a character into the bus */
-int aaio_uart_putchar(char c, FILE *stream) {
+int aaio_uart_putchar(register char c, FILE *stream) {
   if(c == '\n') aaio_uart_putchar('\r', stream);
   loop_until_bit_is_set(UCSR0A, UDRE0);
   UDR0 = c;
@@ -195,10 +195,28 @@ int aaio_uart_getchar(FILE *stream) {
   return (UDR0);
 }
 
+/* put a null-terminated string into the bus */
+void aaio_uart_puts(char *buf) {
+  while(*buf)
+    aaio_uart_putchar(*(buf++), NULL);
+}
+
+/* print a number into the bus */
+void aaio_uart_printnum(register unsigned int value) {
+  register uint8_t d;
+  register uint32_t threshold = 1000000000;
+  for(;threshold > 0;threshold /= 10) {
+    if(value > threshold) {
+      d = (value / threshold) % 10;
+      aaio_uart_putchar('0' + d, NULL);
+    }
+  }
+}
+
 /* get a string of length len from the bus, optionally echoing it back */
-int aaio_uart_gets(char *buf, unsigned int len, char echo) {
-  unsigned int i;
-  char c;
+int aaio_uart_gets(char *buf, register unsigned int len, register char echo) {
+  register unsigned int i;
+  register char c;
   do {
     for(i = 0; i < len - 1; i++) {
       c = (char) aaio_uart_getchar(NULL);
@@ -235,7 +253,7 @@ void aaio_uart_redirect_stdout() {
 /* scan the keyboard and return the associated value */
 /* the definition must be stored in PROGMEM */
 uint8_t aaio_scankey(const uint8_t keypad_def[4][4]) {
-  uint8_t row, col, dirmask;
+  register uint8_t row, col, dirmask;
   for(col = 0; col < 4; col++) {
     AAIO_KEYPAD_DDR = dirmask = 1 << (col + 4);
     AAIO_KEYPAD_PORT = 0xf & ~dirmask;
@@ -273,7 +291,7 @@ static struct {
 };
 
 /* send data to the LCD (in data or command mode) */
-static void _aaio_lcd_write(uint8_t byte, uint8_t is_data) {
+static void _aaio_lcd_write(register uint8_t byte, register uint8_t is_data) {
   register uint8_t i;
   AAIO_LCD_PORT &= ~(1 << AAIO_LCD_SCE); /* enable the controller */
   if(is_data)
@@ -293,11 +311,11 @@ static void _aaio_lcd_write(uint8_t byte, uint8_t is_data) {
   AAIO_LCD_PORT |= (1 << AAIO_LCD_SCE); /* disable the controller */
 }
 
-static void _aaio_lcd_write_cmd(uint8_t cmd) {
+static void _aaio_lcd_write_cmd(register uint8_t cmd) {
   _aaio_lcd_write(cmd, 0);
 }
 
-static void _aaio_lcd_write_data(uint8_t data) {
+static void _aaio_lcd_write_data(register uint8_t data) {
   _aaio_lcd_write(data, 1);
 }
 
@@ -351,19 +369,19 @@ void aaio_lcd_clear(void) {
 }
 
 /* power the LCD on/off */
-void aaio_lcd_power(uint8_t on) {
+void aaio_lcd_power(register uint8_t on) {
   _aaio_lcd_write_cmd(on ? 0x20 : 0x24);
 }
 
 /* set a pixel */
-void aaio_lcd_set_pixel(uint8_t x, uint8_t y, uint8_t value) {
+void aaio_lcd_set_pixel(register uint8_t x, register uint8_t y, register uint8_t value) {
   uint8_t *byte = &_aaio_lcd.screen[(y >> 3) * 84 + x];
   if(value) *byte |= (1 << (y & 7));
   else *byte &= ~(1 << (y & 7));
 }
 
 /* write an ASCII character */
-void aaio_lcd_write_char(char code, uint8_t scale) {
+void aaio_lcd_write_char(register char code, register uint8_t scale) {
   register uint8_t x, y;
   for(x = 0; x < 5*scale; x++)
     for(y = 0; y < 7*scale; y++)
@@ -382,11 +400,11 @@ void aaio_lcd_write_char(char code, uint8_t scale) {
   }
 }
 
-void aaio_lcd_write_string(const char *str, uint8_t scale) {
+void aaio_lcd_write_string(const char *str, register uint8_t scale) {
   while(*str) aaio_lcd_write_char(*str++, scale);
 }
 
-void aaio_lcd_set_cursor(uint8_t x, uint8_t y) {
+void aaio_lcd_set_cursor(register uint8_t x, register uint8_t y) {
   _aaio_lcd.cursor_x = x;
   _aaio_lcd.cursor_y = y;
 }
@@ -402,4 +420,24 @@ void aaio_lcd_render(void) {
 
 #endif
 
+/* PRNG feature */
+
+#ifdef AAIO_FEATURE_RNG
+
+static uint32_t _aaio_rng_state;
+
+void aaio_srand() {
+  _aaio_rng_state = 0xdeadbeef;
+}
+
+uint32_t aaio_rand() {
+	register uint32_t x = _aaio_rng_state;
+	x ^= x << 13;
+	x ^= x >> 17;
+	x ^= x << 5;
+	return _aaio_rng_state = x;
+}
+
+#endif
+
 #endif