MC68HC908JK3 MOTOROLA [Motorola, Inc], MC68HC908JK3 Datasheet - Page 103

• Manufacturer Part Number: MC68HC908JK3
• Description: MC68HC908JK1
• Manufacturer: MOTOROLA [Motorola, Inc]

MC68H(R)C908JL3
MOTOROLA
NOTES:
1. X-tal circuit replaced by RC circuit for MC68HRC908xxx
2. External oscillator must have a 50% duty cycle.
3. Affects high voltage entry to monitor mode only (SW2 at position C):
4. SW2: Position C — High voltage entry to monitor mode.
5. See
SW2: Position D — Bus clock source = X-TAL or RC oscillator.
DB-25
10 F
10 F
SW1: Position A — Bus clock = OSC1 ÷ 4
SW1: Position B — Bus clock = OSC1 ÷ 2
2
3
7
Table 18-4
+
+
1
3
4
2
5
6
for IRQ1 voltage level requirements.
V
—
DD
Input clock = OSC1; Bus clock depends on SW1.
Bus clock = XTALCLK ÷ 4 or RCCLK ÷ 4.
Rev. 1.0
MC145407
RC CIRCUIT
(FOR MC68HRC908xxx)
See
values vs. frequency.
Figure 18-1
Figure 9-1. Monitor Mode Circuit
20
18
17
19
16
15
OSC1
OSC2
+
+
10 F
10 F
for component
Monitor ROM (MON)
V
V
DD
DD
(SEE NOTE 1)
20 pF
X-TAL CIRCUIT
9.8304MHz
(SEE NOTE 2)
(SEE NOTE 4 AND 5)
1
2
6
4
7
MC74HC125
10k
V
DD
20 pF
(SEE NOTE 3)
10k
14
3
5
V
DD
C
D
C
D
C
D
V
DD
+ V
10 k
HI
A
B
SW2
0.1 F
V
DD
10 k
10 k
SW1
0.1 F
10 k
10 k
V
DD
V
Functional Description
DD
V
Monitor ROM (MON)
DD
Technical Data
RST
HC908JL3
HC908JK3
HC908JK1
IRQ1
V
V
OSC1
OSC2
PTB3
PTB0
PTB1
PTB2
DD
SS
103