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User’s Manual U15798EJ2V0UD
CHAPTER 13 10-BIT A/D CONVERTER (
µ
PD780354, 780354Y SUBSERIES)
13.1 10-Bit A/D Converter Functions
The 10-bit A/D converter is a 10-bit resolution converter that converts analog inputs into digital signals. It can control
up to 8 analog input channels (ANI0 to ANI7).
(1) Hardware start
Conversion is started by trigger input (ADTRG: rising edge, falling edge, or both rising and falling edges can
be specified).
(2) Software start
Conversion is started by setting A/D converter mode register 0 (ADM0).
Select one channel for analog input from ANI0 to ANI7 to start A/D conversion. In the case of hardware start, the
A/D converter stops when A/D conversion is completed, and an interrupt request (INTAD0) is generated. In the case
of software start, A/D conversion is repeated. Each time as A/D conversion operation ends, an interrupt request
(INTAD0) is generated.
Figure 13-1. 10-Bit A/D Converter Block Diagram
Note
The valid edge of the external interrupt is specified by bit 3 of the EGP and EGN registers (see
Figure
19-5 Format of External Interrupt Rising Edge Enable Register (EGP), External Interrupt Falling Edge
Enable Register (EGN)
).
ANI0/P10
ANI1/P11
ANI2/P12
ANI3/P13
ANI4/P14
ANI5/P15
ANI6/P16
ANI7/P17
Sample & hold circuit
Series resistor string
Voltage comparator
Controller
Edge
detector
ADTRG/INTP3/P03
3
A/D conversion result
register 0 (ADCR0)
AV
DD
AV
SS
INTAD0
INTP3
Trigger enable
A/D converter
mode register 0 (ADM0)
Analog input channel
specification register 0 (ADS0)
Internal bus
ADS02 ADS01 ADS00 ADCS0 TRG0 FR02 FR01 FR00 EGA01 EGA00
Selector
Tap selector
Edge
detector
Note
Successive
approximation
register (SAR)
ADCE0