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@raybellis
Last active November 12, 2020 12:33
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#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdbool.h>
extern void lcddata(unsigned char n);
static inline uint16_t
display_uint16_t_digit(
uint16_t n, uint16_t div,
bool *leading_zero)
{
char digit = 0;
int shift = (div >= 10000) ? 2 : 3; // prevent overflow
char add = 1 << shift;
div <<= shift;
while (add) {
if (n >= div) {
n -= div;
digit += add;
}
div >>= 1;
add >>= 1;
}
if (digit || *leading_zero) {
lcddata(digit + '0');
*leading_zero = true;
}
return n;
}
void display_uint16_t(uint16_t n)
{
bool zero = false;
n = display_uint16_t_digit(n, 10000, &zero);
n = display_uint16_t_digit(n, 1000, &zero);
n = display_uint16_t_digit(n, 100, &zero);
n = display_uint16_t_digit(n, 10, &zero);
lcddata(n + '0');
}
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