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XC161 Derivatives
Peripheral Units (Vol. 2 of 2)
The Analog/Digital Converter
User’s Manual
16-5
V2.2, 2004-01
ADC_X1, V2.1
Note: The limit values for
f
BC
(see data sheet) must not be exceeded when selecting
ADCTC and
f
ADC
.
16.1.2
Enhanced Mode
In enhanced mode (MD = 1), registers ADC_CTR0, ADC_CTR2, and ADC_CTR2IN
select the basic functions. The register layout differs from the compatibility-mode layout,
but this mode provides more options.
Conversion timing is selected via registers ADC_CTR2(IN), where ADC_CTR2 controls
standard conversions and ADC_CTR2IN controls injected conversions.
RES
12
rw
Conversion Resolution Control
0
10-bit resolution (default after reset)
1
8-bit resolution
ADCTC
[11:6]
rw
ADC Conversion Time Control
Defines the ADC basic conversion clock:
f
BC
=
f
ADC
/ (<ADCTC> + 1)
ADSTC
[5:0]
rw
ADC Sample Time Control
Defines the ADC sample time:
t
S
=
t
BC
×
4
×
(<ADSTC> + 1)
ADC_CTR0
ADC Control Register 0
SFR (FFBE
H
/DF
H
)
Reset Value: 1000
H
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
MD
SAM
PLE
ADCTS
AD
CRQ
AD
CIN
AD
WR
AD
BSY
AD
ST
ADM
CAL
OFF
ADCH
rw
rh
rw
rwh
rw
rw
rh
rwh
rw
rw
rw
Field
Bits
Type
Description
MD
15
rw
Mode Control
0
Compatibility Mode
1
Enhanced Mode
Note: Any modification of control bit MD is forbidden
while a conversion is currently running. User
software must take care.
SAMPLE
14
rh
Sample Phase Status Flag
0
A/D Converter is not in sample phase
1
A/D Converter in sample phase
Field
Bits
Type
Description