catalogue
2, Implementation principle of various special effects of LED
1, Purpose of LED effects
Realize the functions of LED with different flashing effects.
2, Implementation principle of various special effects of LED
First think about the output waveform, and then convert the waveform into data, because whether it is a single chip microcomputer or any processor, the final processing must be data.
For example, if I want to control the LED light to flash once a second, the waveform of the MCU pin controlling the LED is as follows:
The cycle of 500ms high level and 500ms low level can realize the effect that the LED lights flash once per second
The waveform is represented by data in the form of array, which is:
[1500,0500,1500,0500, cycle / single flag]
1 represents pin output high level 500 represents 500 ms of continuous comment
The cycle / word flag can be represented by the largest number. For example, if the array is two bytes, 0xFFFF can be used to represent the cycle and 0xFFFE can be used to represent a single time. It can be easily handled by cooperating with the timer program.
For another complex example, let the LED flash twice every 5 seconds and cycle once. Then the waveform is as follows
100ms high level + 100ms low level + 100ms high level realize LED flash twice, and then 5000ms low level, one cycle.
That is to express the waveform by data in the form of array
[1100,0100,1100,05000, cycle / word flag]
1 represents pin output high level 10 represents the level delay of 100ms, the same is true for 5000.
3, Code implementation
1. The LED effects and led types are encapsulated by enumeration for easy calling
#define LED_EFFECT_END 0xFFFE / / single execution
#define LED_EFFECT_AGN 0xFFFF / / loop execution
// LED type
typedef enum
{
LED1,//0
BUZ,//1
LED_SUM
}LED_TYPEDEF;
// LED command
typedef enum
{
LED_DARK,
LED_LIGHT,
LED_LIGHT_100MS,
LED_BLINK1,
LED_BLINK2,
LED_BLINK3,
LED_BLINK4,
}LED_EFFECT_TEPEDEF;2. Encapsulate the LED command contents with an array
unsigned short Led_Dark[] = {0,10,LED_EFFECT_END};
unsigned short Led_Light[] = {1,10,LED_EFFECT_END};
unsigned short Led_Light100ms[] = {1,10,0,10,LED_EFFECT_END};
unsigned short Led_Blink1[] = {1,10,0,10,LED_EFFECT_AGN,2};
unsigned short Led_Blink2[] = {1,10,0,10,1,10,0,10,1,10,0,200,LED_EFFECT_AGN,6};
unsigned short Led_Blink3[] = {1,30,0,30,LED_EFFECT_AGN,2};
unsigned short Led_Blink4[] = {1,50,0,50,LED_EFFECT_AGN,2};3. LED initialization
void hal_LedInit(void)
{
unsigned char i;
hal_ledConfig();
hal_CreatTimer(T_LED,hal_LedHandle,200,T_STA_START); // Create a 10ms LED timer as a benchmark
for(i=0;i<LED_SUM;i++) // Number of LED s traversed
{
LedLoadFlag[i] = 0; // Set the LED status to idle
pLed[i] = (unsigned short *)Led_Dark; // Turn led_ The dark array is cast to a pointer and the first address value is assigned
LedTimer[i] = *(pLed[i]+1); // Assigns a value to the second address of the array
QueueEmpty(LedCmdBuff[i]); // Empty queue
}
LedMsgInput(LED1,LED_BLINK2,1); // Let the LED lamp achieve a certain effect and execute it immediately
}First, we create a 10ms timer as the benchmark, and then use the for statement to traverse and initialize all the numbers of LED s.
3. LED execution function initialization
void LedMsgInput(unsigned char type,LED_EFFECT_TEPEDEF cmd,unsigned char clr)
{
unsigned char bLedCMD;
if(type >= LED_SUM) // Judge whether the current LED traversal is completed
{
return;
}
bLedCMD = cmd;
if(clr) // Judge whether to execute immediately 1 - execute the current special effect immediately 0 - do not execute immediately
{
QueueEmpty(LedCmdBuff[type]);
LedLoadFlag[type] = 0; // Set queue to idle state
}
QueueDataIn(LedCmdBuff[type],&bLedCMD,1); // List
}
4. System task function
// Task function
void hal_LedProc(void)
{
unsigned char i;
unsigned char cmd;
// Traverse all LED s
for(i=0;i<LED_SUM;i++)
{
if((QueueDataLen(LedCmdBuff[i])>0) && (LedLoadFlag[i]==0)) // Determine whether the queue exists and run flag
{
QueueDataOut(LedCmdBuff[i], &cmd); // Out of line
LedLoadFlag[i] = 1;
switch(cmd)
{
case LED_DARK:
pLed[i] = (unsigned short *)Led_Dark; // Points to the first address of the waveform array
LedTimer[i] = *(pLed[i]+1); // Points to the next address of the waveform array
break;
case LED_LIGHT:
pLed[i] = (unsigned short *)Led_Light;
LedTimer[i] = *(pLed[i]+1);
break;
case LED_LIGHT_100MS:
pLed[i] = (unsigned short *)Led_Light100ms;
LedTimer[i] = *(pLed[i]+1);
break;
case LED_BLINK1:
pLed[i] = (unsigned short *)Led_Blink1;
LedTimer[i] = *(pLed[i]+1);
break;
case LED_BLINK2:
pLed[i] = (unsigned short *)Led_Blink2;
LedTimer[i] = *(pLed[i]+1);
break;
case LED_BLINK3:
pLed[i] = (unsigned short *)Led_Blink3;
LedTimer[i] = *(pLed[i]+1);
break;
case LED_BLINK4:
pLed[i] = (unsigned short *)Led_Blink4;
LedTimer[i] = *(pLed[i]+1);
break;
}
}
}
}5. LED interrupt function
static void hal_LedHandle(void)
{
unsigned char i;
for(i=0;i<LED_SUM;i++) // Number of LED s traversed
{
if(LedTimer[i])
{
LedTimer[i]--; // Counter--
}
if(!LedTimer[i]) // Set arrival time
{
// The timing is up
if(*(pLed[i]+2) == LED_EFFECT_END) // First judge whether the next effect is a single execution flag bit
{
LedLoadFlag[i] = 0; // Set to LED idle
}
else
{
pLed[i]+=2;
if(*pLed[i]==LED_EFFECT_AGN) // Judge whether it is circular execution
{
pLed[i] = pLed[i] - (*(pLed[i]+1)*2); // Re point the first address of the array to pLed
}
LedTimer[i] = *(pLed[i]+1);
}
}
hal_LedDrive[i](*pLed[i]); // Execute LED driver function
}
hal_ResetTimer(T_LED,T_STA_START); // reset timer
}Link: https://pan.baidu.com/s/1oZbqbz8IQD4d6MWc4QsGYQ
Extraction code: nrue