M16C62_M Datasheet, PDF (441/615 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/60 SERIES

A-D Converter
Mitsubishi microcomputers
M16C / 62A Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
2.7.6 Operation of A-D Converter (in repeat mode)
In repeat mode, choose functions from those listed in Table 2.7.6. Operations of the circled items are
described below. Figure 2.7.13 shows timing chart, and Figure 2.7.14 shows the set-up procedure.
Table 2.7.6. Choosed functions
Item
Set-up
Operation clock
φAD
Divided-by-4 fAD / divided-
O _{by-2 fAD / fAD}
Resolution
Analog input pin
Trigger for starting
A-D conversion
O 8-bit / 10-bit
O One of AN0 pin to AN7 pin
O Software trigger
Trigger by ADTRG
Item
Expanded analog
input pin
Sample & Hold
Set-up
O Not used
Either ANEX0 pin or
ANEX1 pin
External operation amplifier
connection mode
Not activated
O _Activated
Operation ^{(1) Setting the A-D conversion start flag to “1” causes the A-D converter to start operating.}
(2) After the first conversion is completed, the content of the successive comparison register
(conversion result) is transmitted to A-D register i. The A-D conversion interrupt request bit
does not go to “1”.
(3) The A-D converter continues operating until the A-D conversion start flag is set to “0” by
software. The conversion result is transmitted to A-D register i every time a conversion is
completed.
φAD
A-D conversion “1”
start flag
“0”
(1) Start A-D conversion
8-bit resolution : 28 φAD cycles
10-bit resolution : 33 φAD cycles
(2) Conversion result is transferred to the A-D register
8-bit resolution : 28 φAD cycles
10-bit resolution : 33 φAD cycles
(3) A-D conversion
is complete
Set to “1” by software
Cleared to “0” by software
A-D register i
Result
Result
A-D conversion
Stop
Convert
Convert
Convert Stop
Note: When φAD frequency is less than 1MHz, sample and hold function cannot be selected.
Conversion rate per analog input pin is 49 φAD cycles for 8-bit resolution and 59 φAD cycles
for 10-bit resolution.
Figure 2.7.13. Operation timing of repeat mode
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