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Chapter 44 A/D Converter
3.Registers of A/D Converter
Cleared by writing "0" or by a reset. (Not cleared at the end of DMA transfer.) Howeverwhen waiting
condition of DMA transfer, this bit cannot be cleared.
Regarding protect function of converted data, see Section “4. Operation of A/D Converter".
[bit 3, 2] STS1, STS0 (Start source select)
These bits initialized "00" by reset.
These bits select the A/D activation source.
In multiple-activation modes, the first activation to occur starts A/D conversion.
The activation source changes immediately on writing to the register. Therefore care is required when
switching activation mode during A/D operation.
The A/D converter detects fallingedges on the external tr igger pin. When externaltr igger levelis "L" and
if these bits are changed to external trigger activation mode, A/D converting may starts.
Selecting the timer selects the 16-bit reload timer 7.
[bit 1] STRT (Start)
Writing "1" to this bit starts A/D conversion (software activation).
Write "1" again to restart conversion.
Initialized to "0" by a reset.
In continuous and stop mode, restarting is not occurred. Check BUSY bit before writing "1". (Activate
conversion after clearing.)
Do not specify forcible termination and software activation (BUSY="0" and STRT="1") at the same time.
[bit 0] reserved bit
Always write "0" to this bit.
A/D control status register 0 (ADCS0)
ADCS0 (ADC0): Address 01A5h (Access:Half-word, Byte)
(See “Meaning of Bit Attribute Symbols (Page No.10)” for details of the attributes.)
[bit 7, 6] MD1, MD0 (A/D converter mode set)
These bits the operation mode.
Single mode: ContinuousA/D conversion from selected channel(s) ANS4 to ANS0 to selected channel(s)
ANE4 to ANE0 with a pause after every conversion cycle.
STS1 STS0 Function
0 0 Software activation [Initial value]
0 1 External trigger pin activation and software activation
1 0 Timer activation and software activation
11
External trigger pin activation, timer activation and software
activation
76543210Bit
MD1 MD0 S10 ACH4 ACH3 ACH2 ACH1 ACH0
00000000
Initial
value
R/WR/WR/WRRRRRAttribute
MD1 MD0 Operating mode
0 0 Single mode ; all restarts conversion during operation enabled
0 1 Single mode ; restarts conversion during operation disabled
1 0 Continuous mode ; restarts conversion during operation disabled
1 1 Stop mode ; restarts conversion during operation disabled