M16C1N Datasheet, PDF (138/238 Pages) Renesas Technology Corp – RENESAS 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/10 SERIES

M16C/1N Group
14. A/D Converter
14.1 One-shot Mode
In one-shot mode, the pin selected using the analog input pin select bit is used for one-shot A/D conver-
sion.
(See Table 14.2.) Figure 14.4 shows the A/D control register in one-shot mode.
Table 14.2 One-shot mode specifications
Item
Specification
Function
The pin selected by the analog input pin select bit is used for one A/D conversion
Start condition
Writing "1" to A/D conversion start flag
Stop condition
• End of A/D conversion (A/D conversion start flag changes to "0")
• Writing "0" to A/D conversion start flag
Interrupt request generation timing End of A/D conversion
Input pin
One of AN0 to AN11, as selected
Reading of result of A/D converter Read A/D register
A/D control register 0 (Note 1)
b7 b6 b5 b4 b3 b2 b1 b0
0
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)
MD0
A/D operation mode
0 : One-shot 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
000
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
1 : 10-bit mode
CKS1 Frequency select bit 1 0 : fAD/2 or fAD/4 is selected
RW
(Note 2) 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: When f(XIN) is over 10 MHz, the flAD frequency must be under 10 MHz by dividing.
Figure 14.4 A/D conversion register in one-shot mode
Rev.1.00 Oct 20, 2004 page 126 of 222
REJ09B0007-0100Z