M16C80 Datasheet, PDF (183/358 Pages) Renesas Technology Corp – RENESAS 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/80 SERIES

M16C/80 Group
21. A/D Converter
(3) Single sweep mode
In single sweep mode, the pins selected using the A/D sweep pin select bit are used for one-by-one A/D
conversion. Table 21.4 shows the specifications of single sweep mode. Figure 21.6 shows the A/D con-
trol register in single sweep mode.
Table 21.4 Single sweep mode specifications
Item
Specification
Function
The pins selected by the A/D sweep pin select bit are used for one-by-one
A/D conversion
Start condition
Writing “1” to A/D converter start flag
Stop condition
• End of A/D conversion (A/D conversion start flag changes to “0”, except
when external trigger is selected)
• Writing “0” to A/D conversion start flag
Interrupt request generation timing End of A/D conversion
Input pin
AN0 and AN1 (2 pins), AN0 to AN3 (4 pins), AN0 to AN5 (6 pins), or AN0 to AN7
(8 pins)
Reading of result of A/D converter Read A/D register corresponding to selected pin
A/D control register 0 (Note)
b7 b6 b5 b4 b3 b2 b1 b0
10
Symbol
ADCON0
Address
039616
When reset
00000XXX2
Bit symbol
CH0
CH1
Bit name
Analog input pin
select bit
Function
Invalid in single sweep mode
RW
CH2
MD0
MD1
A/D operation mode
select bit 0
b4 b3
1 0 : Single sweep mode
TRG
ADST
Trigger select bit
A/D conversion start flag
0 : Software trigger
1 : ADTRG trigger
0 : A/D conversion disabled
1 : A/D conversion started
CKS0
Frequency select bit 0
0 : fAD/4 is selected
1 : fAD/2 is selected
Note: If the A/D control register is rewritten during A/D conversion, the conversion result is indeterminate.
A/D control register 1 (Note 1)
b7 b6 b5 b4 b3 b2 b1 b0
1
0
Symbol
ADCON1
Address
039716
When reset
0016
Bit symbol
Bit name
SCAN0
A/D sweep pin select bit
SCAN1
MD2
A/D operation mode
select bit 1
Function
When single sweep and repeat sweep mode 0
are selected
b1 b0
0 0 : AN0, AN1 (2 pins)
0 1 : AN0 to AN3 (4 pins)
1 0 : AN0 to AN5 (6 pins)
1 1 : AN0 to AN7 (8 pins)
0 : Any mode other than repeat sweep mode 1
RW
BITS
CKS1
VCUT
8/10-bit mode select bit
Frequency select bit 1
(Note 3)
Vref connect bit
0 : 8-bit mode
1 : 10-bit mode
0 : fAD/2 or fAD/4 is selected
1 : fAD is selected
1 : Vref connected
OPA0
OPA1
External op-amp
connection mode
bit (Note 2)
b7 b6
0 0 : ANEX0 and ANEX1 are not used(Note 4)
0 1 : ANEX0 input is A/D converted(Note 5)
1 0 : ANEX1 input is A/D converted(Note 6)
1 1 : External op-amp connection mode(Note 7)
Note 1: If the A/D control register is rewritten during A/D conversion, the conversion result is indeterminate.
Note 2: Neither ‘01’ nor ‘10’ can be selected with the external op-amp connection mode bit.
Note 3: When f(XIN) is over 10 MHz, the fAD frequency must be under 10 MHz by dividing.
Note 4: Set "0" to PSL3_5 and PSL3_6 of the function select register B3.
Note 5: Set "1" to PSL3_5 of the function select register B3.
Note 6: Set "1" to PSL3_6 of the function select register B3.
Note 7: Set "1" to PSL3_5 and PSL3_6 of the function select register B3.
Figure 21.6 A/D conversion register in single sweep mode
Rev.1.00 Aug. 02, 2005 ^{Page 172} of 329
REJ09B0187-0100