Hitachi H8S/2215 Series, Hardware Manual

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Rev. 3.0, 10/02, page 535 of 686
16.2 Input/Output Pins
Table 16.1 summarizes the input pins used by the A/D converter. The AN0 to AN3 and AN14 to
AN15 pins are analog input pins. The AVCC and AVSS pins are the power supply pins for the
analog block in the A/D converter. The Vref pin is the reference voltage pin for the A/D
conversion.
Table 16.1 Pin Configuration
Pin Name Symbol I/O Function
Analog power supply pin AVCC Input Analog block power supply and
reference voltage
Analog ground pin AVSS Input Analog block ground and reference
voltage
Analog reference voltage pin Vref Input Reference voltage pin for the A/D
Analog input pin 0 AN0 Input Analog input pins
Analog input pin 1 AN1 Input
Analog input pin 2 AN2 Input
Analog input pin 3 AN3 Input
Analog input pin 14 AN14 Input
Analog input pin 15 AN15 Input
A/D external trigger input pin
ADTRG
Input External trigger input pin for starting A/D
conversion
16.3 Register Descriptions
The A/D converter has the following registers.
•
A/D data register A (ADDRA)
•
A/D data register B (ADDRB)
•
A/D data register C (ADDRC)
•
A/D data register D (ADDRD)
•
A/D control/status register (ADCSR)
•
A/D control register (ADCR)
16.3.1 A/D Data Registers A to D (ADDRA to ADDRD)
There are four 16-bit read-only ADDR registers; ADDRA to ADDRD, used to store the results of
A/D conversion. The ADDR registers, which store a conversion result for each channel, are
shown in table 16.2.