DF2148ATE20 Renesas Electronics America, DF2148ATE20 Datasheet - Page 672

• Manufacturer Part Number: DF2148ATE20
• Description: IC H8S MCU FLASH 128K 100-QFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8S/2100r

Specifications of DF2148ATE20

• Core Processor: H8S/2000
• Core Size: 16-Bit
• Speed: 20MHz
• Connectivity: Host Interface, I²C, IrDA, SCI
• Peripherals: POR, PWM, WDT
• Number Of I /o: 74
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: FLASH
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Data Converters: A/D 8x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 100-TQFP, 100-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Other names: HD64F2148ATE20; HD64F2148ATE20

Section 20 A/D Converter
20.4.2
Scan mode is useful for monitoring analog inputs in a group of one or more channels. When the
ADST bit is set to 1 by software, or by timer or external trigger input, A/D conversion starts on the
first channel in the group (AN0 when CH2 = 0; AN4 when CH2 = 1). When two or more channels
are selected, after conversion of the first channel ends, conversion of the second channel (AN1 or
AN5) starts immediately. A/D conversion continues cyclically on the selected channels until the
ADST bit is cleared to 0. The conversion results are transferred for storage into the ADDR
registers corresponding to the channels.
When the operating mode or analog input channel must be changed during analog conversion, to
prevent incorrect operation, first clear the ADST bit to 0 in ADCSR to halt A/D conversion. After
making the necessary changes, set the ADST bit to 1 to start A/D conversion again. The ADST bit
can be set at the same time as the operating mode or input channel is changed.
Typical operations when three channels (AN0 to AN2) are selected in scan mode are described
next. Figure 20.4 shows a timing diagram for this example.
1. Scan mode is selected (SCAN = 1), scan group 0 is selected (CH2 = 0), analog input channels
2. When A/D conversion of the first channel (AN0) is completed, the result is transferred to
3. Conversion proceeds in the same way through the third channel (AN2).
4. When conversion of all the selected channels (AN0 to AN2) is completed, the ADF flag is set
5. Steps 2 to 4 are repeated as long as the ADST bit remains set to 1. When the ADST bit is
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AN0 to AN2 are selected (CH1 = 1, CH0 = 0), and A/D conversion is started (ADST = 1)
ADDRA. Next, conversion of the second channel (AN1) starts automatically.
to 1 and conversion of the first channel (AN0) starts again. If the ADIE bit is set to 1 at this
time, an ADI interrupt is requested after A/D conversion ends.
cleared to 0, A/D conversion stops. After that, if the ADST bit is set to 1, A/D conversion
starts again from the first channel (AN0).
Scan Mode (SCAN = 1)