FIFO question ?

[antonius]

Dear Members,

How can I save FIFO ?

I have a psedo code :

for (i = 0; i < NUM_SAMPLES_TO_READ; i++) {

Read FIFO_DATA;

Save IR[15:8];

Read FIFO_DATA;

Save IR[7:0];

Read FIFO_DATA;

Save R[15:8];

Read FIFO_DATA;

Save R[7:0];

}

STOP;

my code :

   for(i=0;i<=number_sample;i++)

  {   

      printf("The output from MAX30100, from 0x09 register (FIFO DATA) : %u \r\n", buffer_rx[i]);

  } 

what should I add there ?

thanks

[antonius]

correct me ?

	 HAL_I2C_Master_Receive(&hi2c2, 0xAF, buffer_rx ,number_sample, 100); //receive 4 bytes from MAX30100
	for(i=0;i<=number_sample;i++)
 {	
		 FIFO_IR_samples[i] = buffer_rx[ ( i << 2 ) ];
 FIFO_IR_samples[i] <<= 8U;
 FIFO_IR_samples[i] |= buffer_rx[ ( i << 2 ) + 1 ];
		 		 printf("Output MAX30100,0x09 register (FIFO DATA) IR : %u \r\n", FIFO_IR_samples[i]);
		 FIFO_RED_samples[i] = buffer_rx[ ( i << 2 ) ];
 FIFO_RED_samples[i] <<= 8U;
 FIFO_RED_samples[i] |= buffer_rx[ ( i << 2 ) + 1 ];
		 
		 printf("Output MAX30100,0x09 register (FIFO DATA) RED : %u \r\n", FIFO_RED_samples[i]);
 } 

[S.Ma]

uint8_t buffer_rx[32*4];
int32_t j;
#define MAKEWORD(b, a)	((uint16_t)(((uint8_t)(a)) | ((uint16_t)((uint8_t)(b))) << 8))
 HAL_I2C_Master_Receive(&hi2c2, 0xAF, buffer_rx ,number_sample*4, 100); //receive 4 bytes from MAX30100
for(i=j=0;i<=number_sample;i++,j+=4)
{	
 FIFO_IR_samples[i] = MAKEWORD( buffer_rx[ j+0 ], buffer_rx[ j+1 ] );
 FIFO_RED_samples[i] = MAKEWORD( buffer_rx[ j+2 ], buffer_rx[ j+3 ] );
 printf("Output MAX30100,0x09 register (FIFO DATA) IR : %u , RED: %u \r\n", FIFO_IR_samples[i]), FIFO_RED_samples[i]);
}

[S.Ma]

There are some code in git to dig in...

https://github.com/kontakt/MAX30100

https://www.arduinolibraries.info/libraries/max30100

 Obsolete item at Digikey...

[antonius]

Is my filter right ?

void filter(sample *s)
{
 uint8_t i;
 uint32_t red = 0;
 uint32_t ired = 0;
 for (i = 0; i < filter_level - 1; i++)
 {
 red += samplebuff[i].red;
 ired += samplebuff[i].ired;
 }
 s->red = (red + s->red) / filter_level;
 s->ired = (ired + s->ired) / filter_level;
}
 
void buffinsert(sample s)
{
 uint8_t i;
 for (i = buff_size - 1; i > 0; i--)
 {
 samplebuff[i].red = samplebuff[i - 1].red;
 samplebuff[i].ired = samplebuff[i - 1].ired;
 }
 samplebuff[0].red = s.red;
 samplebuff[0].ired = s.ired;
}
 
void calacdc(uint16_t *rac, uint32_t *rdc, uint16_t *iac, uint32_t *idc)
{
 uint32_t rmax = samplebuff[0].red;
 uint32_t rmin = samplebuff[0].red;
 uint32_t imax = samplebuff[0].ired;
 uint32_t imin = samplebuff[0].ired;
 
 uint8_t i;
 for (i = 0; i < buff_size; i++)
 {
 if (samplebuff[i].red > rmax)
 rmax = samplebuff[i].red;
 if (samplebuff[i].red < rmin)
 rmin = samplebuff[i].red;
 if (samplebuff[i].ired > imax)
 imax = samplebuff[i].ired;
 if (samplebuff[i].ired < imin)
 imin = samplebuff[i].ired;
 }
 *rac = rmax - rmin;
 *rdc = (rmax + rmin) / 2;
 *iac = imax - imin;
 *idc = (imax + imin) / 2;
}

Inside the loop :

	 HAL_I2C_Master_Receive(&hi2c2, 0xAF, buffer_rx ,number_sample*4, 100); //receive 4 bytes from MAX30100
	for(i=j=0;i<=number_sample;i++,j+=4)
 {	
		 samplebuff[i].ired = buffer_rx[ j ];
		 samplebuff[i].ired <<= 8U;
		 samplebuff[i].ired |= buffer_rx[ j + 1 ];
		 printf("Data %u ",i);
		 printf("Output MAX30100,0x09 register (FIFO DATA) IR : %u \r\n", samplebuff[i].ired);
		 //FIFO_IR_samples[i] = buffer_rx[ j ];
 //FIFO_IR_samples[i] <<= 8U;
 //FIFO_IR_samples[i] |= buffer_rx[ j + 1 ];
		 		 //printf("Output MAX30100,0x09 register (FIFO DATA) IR : %u \r\n", FIFO_IR_samples[i]);
		 //Filter it
		 
		 //samplebufftemp[i].ired = FIFO_IR_samples[i];
		 samplebufftemp[i].ired = samplebuff[i].ired;
		 
		 buffinsert(samplebufftemp[i]);
		 calacdc(&redac, &reddc, &iredac, &ireddc);
		 filter(&samplebufftemp[i]);
		 
		 
		 //FIFO_RED_samples[i] = buffer_rx[ j+2 ];
 //FIFO_RED_samples[i] <<= 8U;
 //FIFO_RED_samples[i] |= buffer_rx[ j+3 ];
		 samplebuff[i].red = buffer_rx[ j ];
		 samplebuff[i].red <<= 8U;
		 samplebuff[i].red |= buffer_rx[ j + 1 ];
		 printf("Data %u ",i);	
		 printf("Output MAX30100,0x09 register (FIFO DATA) RED : %u \r\n", samplebuff[i].red);
 
 	 //samplebufftemp[i].red = FIFO_RED_samples[i];
	 samplebufftemp[i].red = samplebuff[i].red;
		 buffinsert(samplebufftemp[i]); 
	 calacdc(&redac, &reddc, &iredac, &ireddc);
		 filter(&samplebufftemp[i]);
		 
		 float r = (((float)(redac)) / ((float)(reddc))) / (((float)(iredac)) / ((float)(ireddc)));
 if (r >= 0.36 && r < 0.66)
 spo2 = (uint8_t)(107 - 20 * r);
				 
 else if (r >= 0.66 && r < 1)
 spo2 = (uint8_t)(129.64 - 54 * r);
				 printf("SPO2 = %u\r\n",spo2);
				 static uint8_t eachbeatsamplecount = 0; //????????????
 static uint8_t lasttenbeatsamplecount[10]; //?????????????
 static uint32_t last_ired = 0; 
 uint8_t ii;
				
				 eachsamplediff = last_ired - samplebufftemp[i].ired;
 if (eachsamplediff > 50 && eachbeatsamplecount > 12)
 {
 for (ii = 9; ii > 0; ii--)
 lasttenbeatsamplecount[i] = lasttenbeatsamplecount[i - 1];
 lasttenbeatsamplecount[0] = eachbeatsamplecount;
 uint32_t totaltime = 0;
 for (ii = 0; ii < 10; ii++)
 totaltime += lasttenbeatsamplecount[i];
 heartrate = (uint8_t)(60.0 * 10 / 0.02 / ((float)totaltime));
					 printf("Heart Rate = %u\r\n",heartrate);
 eachbeatsamplecount = 0;
 }
 last_ired = samplebufftemp[i].ired;
 eachbeatsamplecount++;
		 
 	 } 

global variable :

	 #define buff_size 50
		sample samplebuff[buff_size];
 sample samplebufftemp[buff_size];
		
		uint8_t heartrate = 0;
		uint8_t spo2 = 0;
 
		uint16_t redac = 0;
		uint32_t reddc = 0;
		uint16_t iredac = 0;
		uint32_t ireddc = 0;
		int16_t eachsamplediff = 0; 
 
#define filter_level 8 
 

[antonius]

I got the output :

Data 0 Output MAX30100,0x09 register (FIFO DATA) IR : 22337 
 
Data 0 Output MAX30100,0x09 register (FIFO DATA) RED : 22337 
 
SPO2 = 0
 
Data 1 Output MAX30100,0x09 register (FIFO DATA) IR : 30557 
 
Data 1 Output MAX30100,0x09 register (FIFO DATA) RED : 30557 
 
SPO2 = 0
 
Data 2 Output MAX30100,0x09 register (FIFO DATA) IR : 38668 
 
Data 2 Output MAX30100,0x09 register (FIFO DATA) RED : 38668 
 
SPO2 = 0
 
Data 3 Output MAX30100,0x09 register (FIFO DATA) IR : 46878 
 
Data 3 Output MAX30100,0x09 register (FIFO DATA) RED : 46878 
 
SPO2 = 0
 
Data 4 Output MAX30100,0x09 register (FIFO DATA) IR : 55170 
 
Data 4 Output MAX30100,0x09 register (FIFO DATA) RED : 55170 
 
SPO2 = 0
 
Data 5 Output MAX30100,0x09 register (FIFO DATA) IR : 63290 
 
Data 5 Output MAX30100,0x09 register (FIFO DATA) RED : 63290 
 
SPO2 = 0
 
Data 6 Output MAX30100,0x09 register (FIFO DATA) IR : 65535 
 
Data 6 Output MAX30100,0x09 register (FIFO DATA) RED : 65535 
 
SPO2 = 0
 
Data 7 Output MAX30100,0x09 register (FIFO DATA) IR : 65535 
 
Data 7 Output MAX30100,0x09 register (FIFO DATA) RED : 65535 
 
SPO2 = 0
 
Data 8 Output MAX30100,0x09 register (FIFO DATA) IR : 0 
 
Data 8 Output MAX30100,0x09 register (FIFO DATA) RED : 0 
 
SPO2 = 0