M16C26 Datasheet, PDF (167/239 Pages) Renesas Technology Corp – 16-BIT CMOS SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/20 SERIES

Udenvdeelropment
Preliminary Specifications Rev.
Specifications in this manual are
A-D Converter
0.9
tentative
and
subject to change.
SINGLE-CHIP 16-BIT
M16C/26 Group
CMOS MICROCOMPUTER
(5) Repeat sweep mode 1
In repeat sweep mode 1, all pins are used for A-D conversion with emphasis on the pin or pins selected
using the A-D sweep pin select bits. Table 1.16.7 shows the specifications of repeat sweep mode 1.
Figure 1.16.8 shows the settings of the A-D control registers in repeat sweep mode 1.
Table 1.16.7. Repeat sweep mode 1 specifications
Item
Specification
Function
Start condition
Stop condition
The pin selected by the analog input pin select bits is used for one A-D conversion
Writing "1" to the A-D conversion start flag
Writing "0" to the A-D conversion start flag
Interrupt request
generation timing
Input pin
Reading of A-D result
None generated
With emphasis on these pins:
AN0, AN0 - AN1 (2 pins), AN0 - AN2 (3 pins), AN0 - AN3 (4 pins)
Read A-D register that corresponds to selected analog input pin (at any time)
A-D control register 0 (Note)
b7 b6 b5 b4 b3 b2 b1 b0
11
Symbol
ADCON0
Address When reset
03D616 00000XXX2
Bit symbol
Bit name
Function
RW
CH0
Analog input pin select Invalid in repeat sweep mode 1
bit
CH1
CH2
MD0
MD1
TRG
ADST
CKS0
A-D operation mode
select bit 0
b4 b3
1 1 : Repeat sweep mode 1
Trigger select bit
0 : Software trigger
1 : ADTRG trigger
A-D conversion start flag 0 : A-D conversion disabled
1 : A-D conversion started
Frequency select bit 0 Refer to table 1.16.2
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
03D716
When reset
0016
Bit symbol
Bit name
SCAN0
A-D sweep pin
select bit
SCAN1
Function
When repeat sweep mode 1 is selected
b1 b0
0 0 : AN0 (1 pin)
0 1 : AN0, AN1 (2 pins)
1 0 : AN0 to AN2 (3 pins)
1 1 : AN0 to AN3 (4 pins)
RW
MD2
BITS
CKS1
A-D operation mode
select bit 1
Set to 1 when this mode is selected
8/10-bit mode select bit 0 : 8-bit mode
1 : 10-bit mode
Frequency select bit1 Refer to table 1.16.2
VCUT Vref connect bit (Note 2) 1 : Vref connected
Nothing is assigned.
In an attempt to write to these bits, write 0. The value, if read, turns out to be 0.
Note 1: If the A-D control register is rewritten during A-D conversion, the conversion result is indeterminate.
Note 2: If the VCUT bit is reset from "0" (Vref unconnected) to "1" (Vref connected), wait for 1 µs or more before starting
A-D conversion.
Figure 1.16.8. A-D conversion control registers in repeat sweep mode 1
Renesas Technology Corp.
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