+/* (CC-BY-NC-SA) ROBIN KRENS - ROBIN @ ROBINKRENS.NL
+ *
+ * $LOG$
+ * 2019/7/20 - ROBIN KRENS
+ * Initial version
+ *
+ * $DESCRIPTION$
+ * Helper functions to set registers
+ *
+ * */
+
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <lib/string.h>
#include <lib/stdio.h>
-#include <sys/mmap.h>
+#include <lib/tinyprintf.h>
+#include <sys/mmap.h>
+#include <sys/robsys.h>
// register set bit at position
void rsetbit(volatile uint32_t * reg, short pos) {
*reg = *reg & ~(0x1 << pos);
}
+// check if a bit is set
int rchkbit(volatile uint32_t * reg, short pos) {
if ((*reg >> pos) & 0x1)
return 1;
}
-/* write value (uint8_t) to register */
-void regw_u8(volatile uint32_t * reg, uint8_t val, short shift, short flag) {
-
- switch(flag) {
- case OWRITE:
- *reg = (val << shift);
- break;
- case SETBIT:
- *reg = *reg | (val << shift);
- break;
- case CLRBIT:
- *reg = *reg & ~(val << shift);
- break;
- }
-}
-
-/* write value (uint32_t) to register */
-void regw_u32(volatile uint32_t * reg, uint32_t val, short shift, short flag) {
-
- switch(flag) {
- case OWRITE:
- *reg = (val << shift);
- break;
- case SETBIT:
- *reg = *reg | (val << shift);
- break;
- case CLRBIT:
- *reg = *reg & ~(val << shift);
- break;
- }
-}
-
-/* Print out the hexidecimal representation of an integer
- After implementation of scanf or sth this will be obsolete. */
-
+/* Deprecated use printf instead
char hexbuf[8];
char * regtohex(uint32_t addr) {
char tmpbuf[6] = {'A', 'B', 'C', 'D', 'E', 'F'};
}
}
return &hexbuf[0];
-}
+} */
+
+// TODO: implement simple scanf functions
int singlehextoreg(char hex) {
int conv = 0;
}
+/* Busy-loop block implementation. Each iteration will take 3 CPU cycles.
+ * Of course, when interrupts are enabled, the exact delay time will be
+ * uncertain.
+ *
+ * Example: for a standard STM32x config board (8MHz) the maximum delay is
+ * 0xFFFF * (1/8,000,000) * 3 = 24.58ms
+ * */
+static void __block(uint16_t count) {
+
+ asm volatile("b1: subs %0, %1, #1" "\n\t"
+ "bne b1" : "=r" (count) : "r" (count));
+}
+
+/* Delay us microsecond
+ * Note: delay includes setup time (about 4 clockcycles), so is quite
+ * inaccurate */
+void _block(uint16_t us) {
+
+ uint16_t count = (us/3) * CLKSPEED_MHZ; // x cycles
+ __block(count);
+
+}
+