M16C1N Datasheet, PDF (139/238 Pages) Renesas Technology Corp – RENESAS 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/10 SERIES

M16C/1N Group
14. A/D Converter
14.2 Repeat Mode
In repeat mode, the pin selected using the analog input pin select bit is used for repeated A/D conversion.
(See Table 14.3.) Figure 14.5 shows the A/D control register in repeat mode.
Table 14.3 Repeat mode specifications
Item
Specification
Function
The pin selected by the analog input pin select bit is used for repeated A/D conversion
Start condition
Writing "1" to A/D conversion start flag
Stop condition
Writing "0" to A/D conversion start flag
Interrupt request generation timing None generated
Input pin
One of AN0 to AN11, as selected (Note 1)
Reading of result of A/D converter Read A/D register (at any time)
Note 1: AN4 to AN7 can be used in the same way as for AN8 to AN11.
A/D control register 0 (Note 1)
b7 b6 b5 b4 b3 b2 b1 b0
01
Symbol
ADCON0
Address
00D616
When reset
00000XXX2
Bit symbol
Bit name
Function
RW
CH0
CH1
CH2
b2 b1 b0
Analog input pin select bit 0 0 0 : AN0 is selected
RW
0 0 1 : AN1 is selected
0 1 0 : AN2 is selected
0 1 1 : AN3 is selected
RW
1 0 0 : AN4, AN8 are selected
1 0 1 : AN5, AN9 are selected
1 1 0 : AN6, AN10 are selected
RW
1 1 1 : AN7, AN11 are selected (Note 2, 3)
MD
A/D operation mode
1 : Repeat mode (Note 2)
RW
select bit 0
ADGSEL0 A/D input group select bit 0 : Port P0 group is selected
1 : Port P1 group is selected
RW
Reserved bit
Set to "0"
RW
ADST
A/D conversion start flag
0 : A/D conversion disabled
1 : A/D conversion started
RW
CKS0
Frequency select bit 0
0 : fAD/4 is selected
1 : fAD/2 is selected
RW
Note 1: If the A/D control register is rewritten during A/D conversion, the conversion result is indeterminate.
Note 2: When changing A/D operation mode, set analog input pin again.
Note 3: AN4 to AN7 and AN8 to AN11 are selected by the A/D input group select bit.
A/D control register 1 (Note 1)
b7 b6 b5 b4 b3 b2 b1 b0
1 0000
Symbol
ADCON1
Address
00D716
When reset
0016
Bit symbol
Bit name
Function
RW
Reserved bit
Set to "0"
RW
BITS
8/10-bit mode select bit 0 : 8-bit mode
RW
(Note 2)
CKS1 Frequency select bit 1 0 : fAD/2 or fAD/4 is selected
RW
(Note 3) 1 : fAD is selected
VCUT VREF connect bit
1 : VREF connected
RW
b7 b6
OPA0 External op-amp
0 0 : ANEX0 and ANEX1 are not used
RW
connection mode bit 0 1 : ANEX0 input is A/D converted
OPA1
1 0 : ANEX1 input is A/D converted
1 1 : External op-amp connection mode
RW
Note 1: If the A/D control register is rewritten during A/D conversion, the conversion result is indeterminate.
Note 2: In repeat mode, only 8-bit mode can be used.
Note 3: When f(XIN) is over 10 MHz, the flAD frequency must be under 10 MHz by dividing.
Figure 14.5 A/D conversion register in repeat mode
Rev.1.00 Oct 20, 2004 page 127 of 222
REJ09B0007-0100Z