762
19.5
Interrupts
The A/D converter generates an A/D conversion end interrupt (ADI) at the end of A/D conversion.
ADI interrupt requests can be enabled or disabled by means of the ADIE bit in ADCSR.
The DTC and DMAC can be activated by an ADI interrupt. Having the converted data read by the
DTC or DMAC in response to an ADI interrupt enables continuous conversion to be achieved
without imposing a load on software.
The A/D converter interrupt source is shown in table 19-6.
Table 19-6 A/D Converter Interrupt Source
Interrupt Source
Description
DTC, DMAC Activation
ADI
Interrupt due to end of conversion
Possible
19.6
Usage Notes
The following points should be noted when using the A/D converter.
Setting Range of Analog Power Supply and Other Pins:
(1) Analog input voltage range
The voltage applied to analog input pin ANn during A/D conversion should be in the range
AVSS
≤
ANn
≤
Vref.
(2) Relation between AVCC, AVSS and VCC, VSS
As the relationship between AVCC, AVSS and VCC, VSS, set AVSS = VSS. If the A/D
converter is not used, the AVCC and AVSS pins must on no account be left open.
(3) Vref input range
The analog reference voltage input at the Vref pin set in the range Vref
≤
AVCC.
If conditions (1), (2), and (3) above are not met, the reliability of the device may be adversely
affected.
Notes on Board Design: In board design, digital circuitry and analog circuitry should be as
mutually isolated as possible, and layout in which digital circuit signal lines and analog circuit
signal lines cross or are in close proximity should be avoided as far as possible. Failure to do so
may result in incorrect operation of the analog circuitry due to inductance, adversely affecting A/D
conversion values.
Содержание H8S/2631
Страница 28: ...xviii Appendix G Package Dimensions 1154 ...
Страница 341: ...316 Transfer SAR or DAR DAR or SAR Block area First block Nth block Figure 9 8 Memory Mapping in Block Transfer Mode ...
Страница 918: ...905 ø DREQ0 DREQ1 tDRQS tDRQH Figure 25 19 DMAC DREQ Input Timing ...
Страница 955: ...943 A 2 Instruction Codes Table A 2 shows the instruction codes ...