board abstraction

firmware/src/utils/utils.cpp

@@ -0,0 +1,137 @@
+/**** Includes ****/
+#include "utils.h"
+
+using namespace util;
+
+/**** Private definitions ****/
+/**** Private constants ****/
+/**** Private variables ****/
+/**** Private function declarations ****/
+#ifndef TESTING
+#endif
+
+/**** Public function definitions ****/
+uint8_t util::invert(uint8_t x)
+{
+	if(x!=0) return 0;
+	else return 1;
+}
+
+uint8_t util::sat_add(uint8_t x, uint8_t y)
+{
+	uint8_t z = x + y;
+	// Check for overflow
+	if((z < x)||(z < y)) return 0xFF;
+	else return z;
+}
+
+uint16_t util::sat_add(uint16_t x, uint16_t y)
+{
+	uint16_t z = x + y;
+	// Check for overflow
+	if((z < x)||(z < y)) return 0xFF;
+	else return z;
+}
+
+uint32_t util::sat_add(uint32_t x, uint32_t y)
+
+{
+	uint32_t z = x + y;
+	// Check for overflow
+	if((z < x)||(z < y)) return 0xFF;
+	else return z;
+}
+
+uint8_t util::sat_subtract(uint8_t x, uint8_t y)
+{
+	uint8_t z = x - y;
+	// Check for underflow
+	if(z > x) return 0;
+	else return z;
+}
+
+uint16_t util::sat_subtract(uint16_t x, uint16_t y)
+{
+	uint16_t z = x - y;
+	// Check for underflow
+	if(z > x) return 0;
+	else return z;
+}
+
+uint32_t util::sat_subtract(uint32_t x, uint32_t y)
+{
+	uint32_t z = x - y;
+	// Check for underflow
+	if(z > x) return 0;
+	else return z;
+}
+
+uint16_t util::sat_cast(uint32_t x)
+{
+	if(x > 0x0000FFFF) return 0xFFFF;
+	else return (uint16_t)x;
+}
+
+uint16_t util::sat_cast(int32_t x)
+{
+	if(x < 0) return 0x0000;
+	else if(x > 0x0000FFFF) return 0xFFFF;
+	else return (uint16_t)x;
+}
+
+uint16_t util::convert_muldivoff(uint16_t raw, uint8_t mul, uint8_t div, int16_t offset)
+{
+	int32_t temp = (int32_t)raw;
+
+	temp = temp * mul;
+	if(div>1) temp /= div;
+	temp += offset;
+
+	return sat_cast(temp);
+}
+
+uint16_t util::sat_mul_kilo(uint16_t xk, uint16_t yk)
+{
+	uint32_t temp = (uint32_t)xk * (uint32_t)yk;
+	temp /= 1000;
+
+	return sat_cast(temp);
+}
+
+uint16_t util::sat_div_kilo(uint16_t top, uint16_t bot)
+{
+	//Sanity check bot
+	if(bot==0) return 0xFFFF; //aka infinity
+
+	uint32_t temp = (uint32_t)top * 1000;
+	temp /= (uint32_t)bot;
+
+	return sat_cast(temp);
+}
+
+uint16_t util::sat_ratio(uint16_t top, uint16_t bot)
+{
+	//Sanity check bot
+	if(bot==0) return 0xFFFF; //aka infinity
+
+	//Easy option
+	if(top>=bot) return 0xFFFF;
+
+	uint32_t temp = (uint32_t)top * 0x0000FFFF;
+	temp /= (uint32_t)bot;
+
+	return sat_cast(temp);
+}
+
+uint16_t util::percent_to_16b(uint8_t percent)
+{
+	uint32_t temp = (uint32_t)percent * 0x0000FFFF;
+	temp /= 100;
+
+	// Limit to 16 bits
+	uint16_t pwm = sat_cast(temp);
+
+	return pwm;
+}
+
+/**** Private function definitions ****/