Heart rate sensor MAX30102

[richard]

But in the program under the registers we are using the AE which is related to write address. Isnt it?

you are trying to create a problem that does not exist there is no such thing as write address or read address in pbp there is only the address
a pbp i2c address is the 7bit manufacturer's address left shifted 1 bit, the only variation is for crappy ancient eeproms where the "page"
address forms part of the address[control] , but bit0 is still under pbp control regardless

you don't quibble the hserout command adding start and stop bits to your serial transmission or even calculating the parity and inserting it also



why should the i2c "high level" commands not be able to set the r/w bit as required, after all that's why you use pbp. it stops you needing to dig into the bowels of i2c transactions

the manual



lets not hear any more of this nonsense

[astanapane]

Thanks Richard,

just wanted to understand it. Now it is clear.

[richard]

now have low pass filtering on pic

73 rpm tonight

[astanapane]

That's really impressed Richard.

Im still working step by step on the code, im still at an early stage.

Just need to understand the methodology.

[richard]

try as i might i cannot detect the relevant peaks reliably

'****************************************************************'*  Name    : MAX30102  FOR PIC 18 DEMO                         *
'*  Author  :  Richard                                          *
'*  Notice  :                                                   *
'*          :                                                   *
'*  Date    : 9/1/2022                                          *
'*  Version : 1.0                                               *
'*  Notes   : MAX30102                                          *        
'*          :18f26k22 @64Mhz                                    *
'****************************************************************
 
  #CONFIG   ;  The PBP configuration for the PIC18F26K22 is:
    CONFIG FOSC     = INTIO67	       
    CONFIG PLLCFG   = OFF	        ;Oscillator multiplied by 4                       
    CONFIG PRICLKEN  = ON	        ;Primary clock enabled
    CONFIG FCMEN     = OFF	        ;Fail-Safe Clock Monitor disabled
    CONFIG IESO      = OFF	        ;Oscillator Switchover mode disabled
    CONFIG  BOREN    = SBORDIS      ; Brown-out Reset enabled in hardware only (SBOREN is disabled)
    CONFIG  WDTEN    = ON           ; WDT is always enabled. SWDTEN bit has no effect                     ;|
    CONFIG  WDTPS    = 32768        ; 1:32768 ---> HERE enable the watchdog timer with a 1:32768 postscale;|
    CONFIG  PWRTEN   = ON
    CONFIG  HFOFST   = ON           ; HFINTOSC output and ready status are not delayed by the oscillator stable status
    CONFIG  MCLRE    = EXTMCLR      ; MCLR pin enabled, RE3 input pin disabled
    CONFIG  LVP      = OFF          ; Single-Supply ICSP disabled
    CONFIG  XINST    = OFF          ; Instruction set extension and Indexed Addressing mode disabled (Legacy mode)
    CONFIG  DEBUG    = OFF          ; Disabled
    CONFIG  CP0 = OFF             ; Block 0 (000800-003FFFh) not code-protected
    CONFIG  CP1 = OFF             ; Block 1 (004000-007FFFh) not code-protected
    CONFIG  CP2 = OFF             ; Block 2 (008000-00BFFFh) not code-protected
    CONFIG  CP3 = OFF             ; Block 3 (00C000-00FFFFh) not code-protected
    CONFIG  CPB = OFF             ; Boot block (000000-0007FFh) not code-protected
    CONFIG  CPD = OFF             ; Data EEPROM not code-protected
    CONFIG  WRT0 = OFF            ; Block 0 (000800-003FFFh) not write-protected
    CONFIG  WRT1 = OFF            ; Block 1 (004000-007FFFh) not write-protected
    CONFIG  WRT2 = OFF            ; Block 2 (008000-00BFFFh) not write-protected
    CONFIG  WRT3 = OFF            ; Block 3 (00C000-00FFFFh) not write-protected
    CONFIG  WRTC = OFF            ; Configuration registers (300000-3000FFh) not write-protected
    CONFIG  WRTB = OFF            ; Boot Block (000000-0007FFh) not write-protected
    CONFIG  WRTD = OFF            ; Data EEPROM not write-protected
    CONFIG  EBTR0 = OFF           ; Block 0 (000800-003FFFh) not protected from table reads executed in other blocks
    CONFIG  EBTR1 = OFF           ; Block 1 (004000-007FFFh) not protected from table reads executed in other blocks
    CONFIG  EBTR2 = OFF           ; Block 2 (008000-00BFFFh) not protected from table reads executed in other blocks
    CONFIG  EBTR3 = OFF           ; Block 3 (00C000-00FFFFh) not protected from table reads executed in other blocks
    CONFIG  EBTRB = OFF           ; Boot Block (000000-0007FFh) not protected from table reads executed in other blocks
 #ENDCONFIG  
 goto overasm  
 asm
PutMulResult?D macro Din
    MOVE?BB   Din, R2
    MOVE?BB   Din + 1, R2 + 1
    MOVE?BB   Din + 2, R0
    MOVE?BB   Din + 3, R0 + 1
    RST?RP
  endm
 endasm
 overasm:


define  OSC 64
OSCCON    = %01110000   ; 16Mhz
OSCTUNE.6 = 1           ; Enable 4x PLL
while ! osccon2.7 :WEND ; to make sure the pll has stabilised before you run any other code


   
TRISC = %11011000                  
ANSELC=0
ANSELB=0
#DEFINE    DEBUGING 1
DEFINE DEBUG_REG PORTB
DEFINE DEBUG_BIT 7
DEFINE DEBUG_BAUD 9600
DEFINE DEBUG_MODE 0






SDA     var portc.4  
SCL     VAR portc.3  




reg        var BYTE
fifo       var byte[6] bank0
addr       var byte 
REVISION   var byte
PARTID     var byte
buffer     var word[384] 
ptr        var byte
btr        var byte
index      var word
average    var byte[4] bank0
ave        var word
peaks      var byte[5]
lastpeak   var word 
lpfdata    var word[192]
result     var word ext
result1    var word ext
@result  =  _fifo 
@result1 =  _fifo + 3
;-----------------------  REGISTER -------------------------
REG_TEMP_INT         con $1F
REG_TEMP_FRAC        con $20
REG_TEMP_CONFIG      con $21
REG_PART_REVISION    con $FE
REG_MODE             con $09
REG_SPO2_CONFIG      con $0A        ;SPO2_ADC_RGE[6:5]SPO2_SR[4:2]LED_PW[1:0]
REG_LED1_PA          con $0C
REG_LED2_PA          con $0D
FIFO_WR_PTR          con $04        ;FIFO_WR_PTR[4:0]
FIFO_RD_PTR          con $06
FIFO_DATA            con $07
FIFO_CONFIG          con $08        ;FIFO_A_FULL[3:0]   SMP_AVE[7:5]
OVF_COUNTER          con $05
STATUS1              con 0          ;A_FULL[7]
INTERRUPT_EN         con 2
' -----------------------------------------------------------------------------|  


#IFDEF  DEBUGING
    LATB.7=1
    PAUSE 2000
    DEBUG 13,10,  "READY"
#ENDIF
    ADDR = $ae     ; addr is  0x57 << 1
    reg = REG_PART_REVISION
    i2cread  SDA,scl,ADDR,reg,[REVISION,PARTID]
    reg = REG_MODE 
    i2cwrite  SDA,scl,ADDR,reg,[3] 
    reg = REG_SPO2_CONFIG
    i2cwrite  SDA,scl,ADDR,reg,[$20]
    reg = REG_LED2_PA 
    i2cwrite  SDA,scl,ADDR,reg,[10]
    reg = REG_LED1_PA 
    i2cwrite  SDA,scl,ADDR,reg,[10]
    reg = FIFO_CONFIG  
    i2cwrite  SDA,scl,ADDR,reg,[16]        
    reg = INTERRUPT_EN  
    i2cwrite  SDA,scl,ADDR,reg,[$E0]
    DEBUG 13,10,  "PART ID: 0X",hex PARTID,"/0X",hex REVISION


start:
    reg= REG_TEMP_CONFIG
    i2cwrite  SDA,scl,ADDR,reg,[1] 
    reg= REG_TEMP_INT        
    i2cread  sda,scl,ADDR,reg,[fifo[0],fifo[1]]
    DEBUG 13,10, "TEMP: ",DEC fifo[0],".",DEC2( fifo[1]<<6)
    GOSUB AQUIRE
    pause 2000
goto start


aquire:
    reg= FIFO_WR_PTR
    i2cwrite  SDA,scl,ADDR,reg,[0]
    reg= FIFO_RD_PTR
    i2cwrite  SDA,scl,ADDR,reg,[0]
    reg = OVF_COUNTER
    i2cwrite sda,scl,ADDR,reg,[0]
    asm
    banksel 0 
    clrf _average
    clrf _average+1
    clrf _average+2
    clrf _average+3
    endasm
 FOR index = 0 TO 255 STEP 0
    btr = 0
    reg = STATUS1
    WHILE (btr & 192) = 0
        i2cread  sda,scl,ADDR,reg,[btr]
    WEND
    reg = FIFO_WR_PTR
    i2cread  SDA,scl,ADDR,reg,[Ptr]
    reg = FIFO_RD_PTR
    i2cread  SDA,scl,ADDR,reg,[btr]
    btr = (ptr - btr) &  31
    WHILE btr
        reg = FIFO_DATA           ;---------ir----------;===========red===========
        i2cread  sda,scl,ADDR,reg,[FIFO[5],FIFO[4],FIFO[3],FIFO[2],FIFO[1],FIFO[0]]
        asm         ;ROTATE READING TO GET SUFFICIENT RESOLOUTION INTO lower WORD
    banksel 0
    bcf STATUS,C
    RRCF  _fifo + 2 ,f
    RRCF  _fifo + 1 ,f
    RRCF  _fifo     ,f
    bcf STATUS,C
    RRCF  _fifo + 2 ,f
    RRCF  _fifo + 1 ,f
    RRCF  _fifo     ,f
    bcf STATUS,C
    RRCF  _fifo + 5 ,f
    RRCF  _fifo + 4 ,f
    RRCF  _fifo + 3 ,f
    bcf STATUS,C
    RRCF  _fifo + 5 ,f
    RRCF  _fifo + 4 ,f
    RRCF  _fifo + 3 ,f
    
    movf  _fifo  ,w         ;RED AVERAGE
    addwf  _average,f
    movf  _fifo + 1 ,w
    bnc s1   
    incf   _average + 1,f
s1    
    addwf  _average + 1,f
    movf  _fifo + 2 ,w
    bnc    s2
    incf   _average + 2,f
s2    
    bnc     s3
    incf   _average + 3 ,f
s3  
endasm
        buffer[index] = result  ;red
        index = index + 1
        buffer[index] = result1 ;ir
        index = index + 1
        btr = btr - 1
    WEND
NEXT  
    DEBUG 13,10,hex2 average[3],hex2 average[2],hex2 average[1],hex2 average  
    @ PutMulResult?D _average   ;RED AVERAGE
    ave  = DIV32 128            ;RED AVERAGE
    reg = OVF_COUNTER
    i2cread sda,scl,ADDR,reg,[reg ] 
    DEBUG 13,10,"OverFlows ",DEC reg,9,dec ave,9,hex ave
    FOR index = 0 TO 255 STEP 0
        ave = (ave ** 62259) + (buffer[index] ** 3276 )
        lpfdata[index>>1]=ave 
              ;.....lpf..;;;;----red-----;;;;======-ir-========
        DEBUG 13,10,dec ave,9,dec buffer[index],9,dec buffer[index+1]
        index = index + 2
    NEXT 
 RETURN

[mpgmike]

In Post #44 your low-pass filter seemed to work perfectly, then in Post #49, it seemed a bit overdone. Then in Post #51 it looks like the low-pass filter is acting like a 500F capacitor! I didn't look at the code, but maybe you could back off on the filter settings for a clearer reading.

[richard]

but maybe you could back off on the filter settings for a clearer reading.

i have tried many variations , the added aggressiveness of the filter is an attempt to remove the unwanted "little" peaks
what looks like a nice picture of on a graph does not mean peak detection is easier.
some of the lp filtering is just added in with excel also, even tried using trend lines in attempt at detecting pos and neg zero crossings
that's still not 100% effective. dsp is not my forte, dc drift in the readings can be neg or pos going or both or zero.
fft was a failure because i cannot remove the dc component effectively. i need a better method i have no effective strategy