Fujitsu F2MC-8L MB89620 Series Hardware Manual page 282

n Program Example for Sense Function
l Processing description
• Generates an interrupt if the analog voltage input to the AN0 pin is less than 3.0 V.
• Perform continuous activation of the sense function synchronized with pulses input to the
ADST pin.
• For analog power supply voltage (AV
register value of 0A9H gives a compare voltage of 3.0 V.
l Coding example
DDR3
PDR5
ADC1
ADC2
ADCD
AN0
ADI
ADMV
AD
EXT
ILR3
INT_V
IRQ9
INT_V
;-----Main program----------------------------------------------------------------------------------------------------------------------------------------
AD_WAIT
;-----Interrupt processing routine----------------------------------------------------------------------------------------------------------------------
WARI
;---------------------------------------------------------------------------------------------------------------------------------------------------------------
MB89620 series
EQU 000DH
EQU 0010H
EQU 0020H
EQU 0021H
EQU 0022H
EQU PDR5:0
EQU ADC1:3
EQU ADC1:2
EQU ADC1:0
EQU ADC2:1
EQU 007EH
DSEG ABS
ORG 0FFE8H
DW WARI
ENDS
CSEG
:
SETB AN0
MOV DDR3,#00000000B
CLRI
MOV ILR3,#11110111B
CLRB EXT
BBS ADMV,AD_WAIT
MOV ADCD,#9AH
MOV ADC1,#00000000B
MOV ADC2,#00011111B
SETI
:
CLRB ADI
PUSHW A
XCHW A,T
PUSHW A
:
User processing
:
POPW A
XCHW A,T
POPW A
RETI
ENDS
END
) = reference voltage (AVR) = 5.0 V, an ADCD
CC
; Port 3 data direction register
; Port 5 data register
; A/D control register 1
; A/D control register 2
; A/D data register
; Define the AN0 analog input pin.
; Define the interrupt request flag bit.
; Define the conversion-in-progress flag bit.
; A/D converter activation bit (software activation)
; Define the continuous activation enable bit.
; Set interrupt level setting register 3.
; [DATA SEGMENT]
; [CODE SEGMENT]
; Stack pointer (SP) etc. are already initialized.
; Set P50/AN0 pin as an analog input pin.
; Set P30/ADST pin as an input.
; Disable interrupts.
; Set interrupt level (level 1).
; Disable continuous activation.
; Loop to check that the A/D converter is halted.
; Set compare voltage data (3.0 V).
; Select analog input channel 0 (AN0), clear interrupt request flag,
set compare condition (interrupt if the input voltage
is lower), and do not activate by software.
; Select external clock, enable interrupt request output, select the
sense function, and enable continuous activation.
; Enable interrupts.
; Clear interrupt request flag.
CHAPTER 13 A/D CONVERTER
13
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