mc68hc908ap8a Freescale Semiconductor, Inc, mc68hc908ap8a Datasheet - Page 116

• Manufacturer Part Number: mc68hc908ap8a
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Monitor Mode (MON)
116
NOTES:
1. Monitor mode entry method:
2. Affects high voltage entry to monitor mode only (SW2 at position C):
3. See
1 µF
1 µF
2
3
5
DB9
SW2: Position C — High voltage entry (V
SW2: Position D — Reset vector must be blank ($FFFE:$FFFF = $FF)
SW1: Position A — Bus clock = OSC1÷4
SW1: Position B — Bus clock = OSC1÷2
Table 22-4
+
+
1
3
4
5
7
8
C1+
C1–
C2+
C2–
for V
MAX232
TST
Bus clock depends on SW1 (note 2).
Bus clock = 1.2288MHz.
voltage level requirements.
GND
V
V+
CC
V–
16
15
2
10
6
9
V
EXT OSC
MUST BE USED IF SW2 IS AT POSITION C.
CONNECT TO OSC1, WITH OSC2 UNCONNECTED.
DD
+
+
MC68HC908AP A-Family Data Sheet, Rev. 3
1 µF
TST
1 µF
Figure 8-1. Monitor Mode Circuit
2
); must use external OSC
74HC125
1
V
+
REG
3
1 µF
74HC125
4.9152MHz/9.8304MHz
6
V
TST
4
5
XTAL CIRCUIT
6–30 pF
(50% DUTY)
V
DD
10 k
4.9152MHz
1 k
(SEE NOTE 2)
OSC1
8.5 V
6–30 pF
0.1 µF
10k
10 k
C
D
A
B
1M
V
V
DD
DD
0.22 µF
SW2
SW1
10k
1 k
(SEE NOTE 1)
10 k
0.1 µF
Freescale Semiconductor
10k
V
DD
V
0.01 µF
DD
RST
HC908AP
V
V
V
V
V
V
V
CGMXFC
OSC1
OSC2
IRQ1
PTA0
PTA1
PTB0
PTA2
DD
DDA
REFH
REG
REFL
SS
SSA