XC68HC705JJ7 Motorola, XC68HC705JJ7 Datasheet - Page 130

• Manufacturer Part Number: XC68HC705JJ7
• Description: MICROCONTROLLER
• Manufacturer: Motorola

Analog Subsystem
Advance Information
130
Point
0
1
2
3
COMP2
(TCAP)
Begin initial discharge and select mode 2
by clearing CHG and ATD1 and setting
ATD2 in the ACR. Also set ICEN bit in
ACR and IEDG bit in TCR.
V
Stop discharge and begin charge when
the next TOF sets the CHG control bit in
ACR.
V
output trips, setting CPF2 and CMP2,
which causes an ICF from the timer and
clears the CHG control bit in ACR. Must
clear CPF2 to trap next CPF2 flag.
V
CHG
OCF
TOF
CAP
CAP
CAP
ICF
V
X
falls to V
rises to V
Figure 8-10. A/D Conversion — TOF/ICF Control (Mode 2)
0
SS
X
Action
.
and comparator 2
1
(MIN)
t
DIS
t
DIS
2
Analog Subsystem
t
CHG
Software write
Wait out minimum t
Timer TOF sets the CHG control
bit in the ACR.
Wait out t
Timer ICF clears the CHG control
bit in the ACR.
Software/Hardware Action
CHG
3
time.
MC68HC705JJ7 • MC68HC705JP7 — REV 4
1
DIS
(MIN)
t
DIS
time.
2
Software
V
Free-running timer
counter overflow, f
V
Dependent Variable(s)
MAX
X
, I
V
V
MAX
CHG
X
, I
=
DIS
, C
t
CHG
, C
C
EXT
EXT
x I
EXT
MOTOROLA
CHG
OSC