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IMPLEMENTATION OF SIGMA-DELTA ADC WITH ST7FLITE05/09

ld ATRH,a

ld a,#$70

ld ATRL,a

ld a,#%00010010

ld ATCSR,a

rim

;**********************************************************************

;Main loop of the program

;**********************************************************************

IDLE:

btjf FLAGS0,#Nw_adc,Idle ; waiting for the conversion result

bres FLAGS0,#Nw_adc

; new result

; sending the conversion result

; through RS

ld a,#$FF

; frame format:

call Send_rs

;0FFh,0FFh,Rez_H,Rez_L

ld a,#$FF

call Send_rs

ld a,Rez_h

call Send_rs

ld a,Rez_l

call Send_rs

jra IDLE

;**********************************************************************

;Interrupts

;**********************************************************************

; delta/sigma conversion

; sampling of 1 bit with period of 50us

; conversion result- 10 bit word, received every (1024*50us)=51,2ms

;**********************************************************************

timoverfl_rt:

bres ATCSR,#2

; cancelling of the interrupt re-

; quest

ld a,#00000100

; adding the amplifier into the A/D

; processing

ld ADCCAMP,a

ld a,#%01100001

; voltage measurement at AIN1

ld ADCCSR,a

loop_adc:

btjf ADCCSR,#7,loop_adc

ld a,ADCDR

cp a,#$37

; comparison U_ain1 z 037h

jrc set_Dlt

bres PBDR,#Dlt_out

; U_ain1>037h

inc Adc_l

; increase of the conversion result