Rev. 1.0, 02/00, page 519 of 1141
Conversion frequency
Note: IRQ sampling;
Conversion period (134 or 266 states)
Interrupt request flag
IRQ sampling
(CPU)
States
Instruction execution
MOV.B
WRITE
Start flag
When conversion ends, the start flag is cleared and the interrupt request flag is
set. The CPU recognizes the interrupt in the last execution state of an instruction,
and executes interrupt exception handling after completing the instruction.
Figure 24.2 Internal Operation of A/D Converter
Bit 6
Reserved: This bit cannot be modified and is always read as 1.
Bits 5 and 4
Hardware Channel Select (HCH1, HCH0): These bits select the analog input
channel that is converted by hardware triggering or triggering by an external input. Only channels
AN8 to ANB are available for hardware- or external-triggered conversion.
Bit 5
Bit 4
HCH1
HCH0
Analog Input Channel
0
AN8
(Initial value)
0
1
AN9
0
ANA
1
1
ANB