2018-06-21HOLTEK HT49R70A-1 Source Code analysis

Cange note：

 “Reading TMR1H will latch the contents of TMR1H and TMR1L counter to the destination”? For example < MOV a,TMR1H >, but accumulator only 8-bit, how can latch TMR1H and TMR1L

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Read_Temp:

IFNDEF  RELEASE_VERSION

    mov a,lastram

    mov temperature,a  ;store calculated temperatur (table pos.)

    ret

ENDIF

    snz flag3.f_read_temp

    ;jmp    read_temp_end

    ret                    ;V05_Joey

    clr flag3.f_read_temp

    mov a,4

    mov temploop,a

    clr ntcl

    clr ntch

loop_ntc:

    clr EMI        ;disable all interrupts

    set outa.RV    ;set all I/Os in normal pos

    set outa.NTC

    clr outa.TR

    set outa.RS

    mov a,outa

    mov PA,a

    call    delay_100us ;time to discharge cap

    clr TMR1

    clr TMR0     

    set TMR1C.4    ;enable TMR1

    set TMR0C.4        ;enable TMR0

    clr outa.NTC        ;now test NTC time

    set outa.TR

    mov a,outa

    mov PA,a

    nop

    nop

wait_AD_NTC:

    sz  PA.Rs  ;

    jmp wait_AD_NTC

    clr TMR0C.4 ;disable TMR0 

    clr TMR1C.4 ;disable TMR1

    set outa.NTC        ;discarge cap

    clr outa.TR

    mov a,outa

    mov PA,a

    mov a,TMR0

    addm    a,ntcl

    mov a,TMR1

    adcm    a,ntch

    dec temploop

    snz z

    jmp loop_ntc

    clr c

    rrc ntch

    rrc ntcl    ;NTC / 2

    clr c

    rrc ntch 

    rrc ntcl    ;NTC / 4