1 #include "display_basic.h"
5 /* delay routine written in assembly so we know what we're really getting.
6 * each inner loop should take ~1 ms to execute.
7 * 15 cycles * (1/4.9152Mhz) * 327 = 0.997 ms + a little bit on the fringes.
9 * XXX - how do we know gcc isn't optimising this? it seems to optimise after
10 * parsing C -> asm, but before asm -> machine code.
12 //asm volatile ("pshx\npsha\npshb\n"); /* save registers */
13 asm volatile ("ldx %0\n" :: "m" (ms) : "x");
16 //" ldd #327\n" /* 3 */
18 "delay_inner_loop:\n" /* 15 cycles each */
19 " cpd #0x0000\n" /* 5 */
20 " beq delay_inner_loop_end\n" /* 3 */
21 " subd #0x0001\n" /* 4 */
22 " bra delay_inner_loop\n" /* 3 */
23 "delay_inner_loop_end:\n"
25 " beq delay_out\n" /* 3 */
26 " bra delay_loop\n" /* 3 */
27 "delay_out:\n" ::: "x", "d");
33 u8 my_strlen(char* s) {
39 void my_strncpy(char* dst, char* src, u8 max_size) {
41 for (i = 0; src[i] && i < max_size; i++) dst[i] = src[i];
42 if (src[i] == 0 && i < max_size) dst[i] = 0; /* null terminator */
45 bool my_strncmp(char* a, char* b, u8 len) {
47 for (i = 0; i < len; i++) {
48 if (*a != *b) return 0;
55 void my_memcpy(char* dst, char* src, u8 size) {
57 for (i = 0; i < size; i++) dst[i] = src[i];
60 void my_memset(char* dst, u8 val, u16 count) {
62 for (c = dst; c < dst+count; c++) *c = val;