From 0f7a7e93ded497c0fd5a47f5e42633eae5d2365d Mon Sep 17 00:00:00 2001 From: Josh Rahm Date: Wed, 18 Nov 2020 21:12:50 -0700 Subject: add lib.h/lib.c --- 02-usart/include/lib.h | 10 +++++++++ 02-usart/src/lib.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 66 insertions(+) create mode 100644 02-usart/include/lib.h create mode 100644 02-usart/src/lib.c diff --git a/02-usart/include/lib.h b/02-usart/include/lib.h new file mode 100644 index 0000000..be0e8e9 --- /dev/null +++ b/02-usart/include/lib.h @@ -0,0 +1,10 @@ +#ifndef LIB_H_ +#define LIB_H_ + +#include + +void hexify(uint32_t v, char* into); + +void decimalify(int v, char* into); + +#endif diff --git a/02-usart/src/lib.c b/02-usart/src/lib.c new file mode 100644 index 0000000..d5d81da --- /dev/null +++ b/02-usart/src/lib.c @@ -0,0 +1,56 @@ +#include "lib.h" + +#define nybble_to_hex(n) \ + ((n) < 10 ? 0x30 + (n) : ('A' + ((n) - 10))) + +void hexify(uint32_t v, char* into) +{ + into += 8; + + *(into--) = 0; + + *(into--) = nybble_to_hex(v & 0x0F); + v >>= 4; + *(into--) = nybble_to_hex(v & 0x0F); + v >>= 4; + *(into--) = nybble_to_hex(v & 0x0F); + v >>= 4; + *(into--) = nybble_to_hex(v & 0x0F); + v >>= 4; + + *(into--) = nybble_to_hex(v & 0x0F); + v >>= 4; + *(into--) = nybble_to_hex(v & 0x0F); + v >>= 4; + *(into--) = nybble_to_hex(v & 0x0F); + v >>= 4; + *into = nybble_to_hex(v & 0x0F); + v >>= 4; +} + +void decimalify(int v, char* into) +{ + int c = 0; + int i; + + if (v == 0) { + *(into ++) = '0'; + *into = 0; + return; + } else { + while (v > 0) { + *(into ++) = 0x30 + (v % 10); + v /= 10; + ++ c; + } + } + *into = 0; + + into -= c; + for (i = 0; i < c / 2; ++ i) { + char tmp = into[i]; + into[i] = into[c - i - 1]; + into[c - i - 1] = tmp; + } + +} -- cgit