Holtek HT46R47, Руководство пользователя

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HT46R46/C46/R47/C47/R48A/C48A/R49
Rev. 1.41 32 December 30, 2008
Example: using an interrupt method to detect the end of conversion for the HT46R46
clr EADI ; disable ADC interrupt
mov a,00000001B
mov ACSR,a ; setup the ACSR register to select fSYS/8 as
; the A/D clock
mov a,00100000B ; setup ADCR register to configure Port PB0~PB3
; as A/D inputs
mov ADCR,a ; and select AN0 to be connected to the A/D
; converter
:
; As the Port B channel bits have changed the
; following START
; signal (0-1-0) must be issued within 10
; instruction cycles
:
Start_conversion:
clr START
set START ; reset A/D
clr START ; start A/D
clr ADF ; clear ADC interrupt request flag
set EADI ; enable ADC interrupt
set EMI ; enable global interrupt
:
:
:
; ADC interrupt service routine
ADC_ISR:
mov acc_stack,a ; save ACC to user defined memory
mov a,STATUS
mov status_stack,a ; save STATUS to user defined memory
:
:
mov a,ADR ; read conversion result value from the ADR
; register
mov adr_buffer,a ; save result to user defined register
:
:
EXIT_INT_ISR:
mov a,status_stack
mov STATUS,a ; restore STATUS from user defined memory
mov a,acc_stack ; restore ACC from user defined memory
reti