H8SSLASH2218 datasheet(590/750 Pages) RENESAS

590 / 750 page

Section 15 A/D Converter

Rev.6.00 Jun. 03, 2008 Page 542 of 698

REJ09B0074-0600

15.5

Operation

The A/D converter operates by successive approximation with 10-bit resolution. It has two

operating modes; single mode and scan mode. When changing the operating mode or analog input

channel, in order to prevent incorrect operation, first clear the bit ADST to 0 in ADCSR. The

ADST bit can be set at the same time as the operating mode or analog input channel is changed.

15.5.1

Single Mode

In single mode, A/D conversion is to be performed only once on the specified single channel. The

operations are as follows.

1. A/D conversion is started when the ADST bit is set to 1, according to software or external

trigger input.

2. When A/D conversion is completed, the result is transferred to the corresponding A/D data

3. On completion of conversion, the ADF bit in ADCSR is set to 1. If the ADIE bit is set to 1 at

this time, an ADI interrupt request is generated.

4. The ADST bit remains set to 1 during A/D conversion. When A/D conversion ends, the ADST

bit is automatically cleared to 0 and the A/D converter enters the wait state.

ADIE

ADST

ADF

State of channel 0 (AN0)

A/D

conversion

starts

ADDRA

ADDRB

ADDRC

ADDRD

State of channel 1 (AN1)

State of channel 2 (AN2)

State of channel 3 (AN3)

Note: * Vertical arrows ( ) indicate instructions executed by software.

Set*

Clear*

A/D conversion result 1

A/D conversion

A/D conversion result 2

Read conversion result*

Idle

A/D conversion

Set*

Figure 15.3 A/D Conversion Timing (Single-Chip Mode, Channel 1 Selected)

H8S/2218 数据表(PDF) 590 Page - Renesas Technology Corp

H8S/2218 数据表(HTML) 590 Page - Renesas Technology Corp

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

数据表下载