00001 /*@{*//*@}*/ 00014 00015 /******************************************************************************/ 00016 /* Includes (#include) */ 00017 #include <avr/io.h> 00018 #include <avr/interrupt.h> 00019 00020 /* Own header files */ 00021 #include "xtypes.h" 00022 #include "global.h" 00023 00024 #include "timer.h" 00025 #include "memory.h" 00026 00027 #define EXPORT 00028 #include "speed.h" 00029 #undef EXPORT 00030 00031 /******************************************************************************/ 00032 /* Constants (#define) *//*@{*/ 00033 00036 #define MAX_RELIABLE_SPEED 70U 00037 00038 /* End: Constants (#define) *//*@}*/ 00039 /******************************************************************************/ 00040 00041 /******************************************************************************/ 00042 /* Macro definitions (#define) *//*@{*/ 00043 00045 #define SPEED_INT_ENABLE() EIMSK |= (1<<INT0); 00046 00048 #define SPEED_INT_DISABLE() EIMSK &= ~(1<<INT0); 00049 /* End: Macro definitions (#define) *//*@}*/ 00050 /******************************************************************************/ 00051 00052 /******************************************************************************/ 00053 /* Basic types (typedef) *//*@{*/ 00054 /* End: Basic types (typedef) *//*@}*/ 00055 /******************************************************************************/ 00056 00057 /******************************************************************************/ 00058 /* Local constants (const) *//*@{*/ 00059 /* End: Local constants (const) *//*@}*/ 00060 /******************************************************************************/ 00061 00062 /******************************************************************************/ 00063 /* Local variables *//*@{*/ 00064 00066 STATIC VOLATILE UINT32 mg_u32TickTime; 00067 00069 STATIC VOLATILE UINT32 mg_u32Rpm; 00070 00072 STATIC VOLATILE UINT32 mg_u32Distance; 00073 00075 STATIC UINT16 mg_u16WheelSize; 00076 00078 STATIC UINT8 mg_u8NumMagnetsTacho = DEFAULT_MAGNET_NUMBER_TACHO; 00079 00080 /* End: Local variables *//*@}*/ 00081 /******************************************************************************/ 00082 00083 /******************************************************************************/ 00084 /* Global variables *//*@{*/ 00085 /* End: Global variables *//*@}*/ 00086 /******************************************************************************/ 00087 00088 /******************************************************************************/ 00089 /* Prototype declarations */ 00090 /* End: Prototype declarations */ 00091 /******************************************************************************/ 00092 00093 /******************************************************************************/ 00094 /* Local functions *//*@{*/ 00095 00096 /* ****************************************************************************/ 00111 /* ****************************************************************************/ 00112 ISR (SIG_INTERRUPT0) 00113 { 00114 LOCAL_STATIC UINT32 u32CurrentTime; 00115 UINT32 u32DiffTime; 00116 00117 SPEED_INT_DISABLE(); 00118 00119 u32CurrentTime = timer_GetSystemTime(); 00120 u32DiffTime = u32CurrentTime - mg_u32TickTime; 00121 00122 /* Maybe there will be false sensor signals from keybouncing. 00123 To filter these out we use a maximum speed definition that gives a 00124 minimum diff time between two sensor signals: 00125 00126 wheel_size[mm] * 3.6 00127 -------------------------------------------- 00128 max_reliable_speed[km/h] * number_of_magnets 00129 00130 And to avoid floating point numbers we sustitute 3.6 with 36/10. 00131 */ 00132 if(u32DiffTime >= ( (mg_u16WheelSize * 36U) / 00133 (MAX_RELIABLE_SPEED * 10U * mg_u8NumMagnetsTacho) ) 00134 ) 00135 { 00136 mg_u32TickTime = u32CurrentTime; 00137 mg_u32Rpm = ONE_MINUTE_MS / u32DiffTime / mg_u8NumMagnetsTacho; 00138 mg_u32Distance += mg_u16WheelSize; 00139 } 00140 00141 SPEED_INT_ENABLE(); 00142 } 00143 00144 /* End: Local functions *//*@}*/ 00145 /******************************************************************************/ 00146 00147 /******************************************************************************/ 00148 /* Global functions *//*@{*/ 00149 00150 /* ****************************************************************************/ 00162 /* ****************************************************************************/ 00163 void speed_Init (void) 00164 { 00165 mg_u8NumMagnetsTacho = memory_Get()->u8NumMagnetsTacho; 00166 if(0U == mg_u8NumMagnetsTacho) 00167 { 00168 mg_u8NumMagnetsTacho = 1U; // to avoid division by 0 00169 } 00170 00171 INT0_DDR &= ~(1U << INT0_BIT); /* set ext. interrupt pin as input pin */ 00172 00173 /* the effective wheel size is the actual wheel size divided by the number of 00174 magnets */ 00175 mg_u16WheelSize = ( memory_Get()->u16WheelSize / mg_u8NumMagnetsTacho ); 00176 00177 /* setup for falling edge */ 00178 EICRA |= (1<<ISC01); 00179 EICRA &= ~(1<<ISC00); 00180 00181 mg_u32TickTime = 0U; 00182 mg_u32Rpm = 0U; 00183 mg_u32Distance = 0U; 00184 00185 /* enable interrupt */ 00186 SPEED_INT_ENABLE(); 00187 } 00188 00189 /* ****************************************************************************/ 00200 /* ****************************************************************************/ 00201 UINT32 speed_GetRpm (void) 00202 { 00203 UINT32 u32Ret; 00204 cli(); 00205 u32Ret = mg_u32Rpm; 00206 sei(); 00207 return (u32Ret); 00208 } 00209 00210 00211 /* ****************************************************************************/ 00222 /* ****************************************************************************/ 00223 UINT32 speed_GetDistance (void) 00224 { 00225 UINT32 u32Ret; 00226 cli(); 00227 u32Ret = mg_u32Distance; 00228 sei(); 00229 return (u32Ret); 00230 } 00231 00232 00233 /* ****************************************************************************/ 00248 /* ****************************************************************************/ 00249 void speed_CheckTimeout (UINT32 u32SystemTime) 00250 { 00251 UINT32 u32TickTime; 00252 cli(); 00253 u32TickTime = mg_u32TickTime; 00254 sei(); 00255 if(u32SystemTime >= (u32TickTime + SPEED_TIMEOUT)) 00256 { 00257 cli(); 00258 mg_u32Rpm = 0U; 00259 sei(); 00260 } 00261 } 00262 00263 /* End: Global functions *//*@}*/ 00264 /******************************************************************************/ 00265 00266 /**** Last line of code ****/
1.7.2