Brother HL-600 Service Manual page 15

1.3 Main PCB
1.3.1 CPU
The CPU is a Motorola MC68EC000FN16 which is driven with a clock frequency of 15.3
MHz. This clock frequency is made by dividing the source clock of 30.67 MHz into two.
The address bus is 23 bits of A1 to A23, and the data bus is 16 bits. The total memory
space is 16 MBytes.
#2 MC68EC000FN16
NC 22
VCC
NC
VCC
21
(
05) RESET
RESET VCC
20
HALT
16
(
-05F)
SCLK CLK
CND
11
(
-05E)
DTACK DTACK
CND
CND
13
(
-05F) BR BR
CND
CND
24
BERR
+5V
23
(
-05F) AVEC AVEC
27
(
-05F)
IPL0 IPL0
26
( -05F)
IPL1
IPL1
25
(
-05F)
IPL2
IPL2
NC 31
A0
MODE
A1 32
A1
A2 33
A2
A3 34
A3
A4 36
A4
A5 37
A5
38
A6
A6
A7 39
A7
A8 40
A8
A9 41
A9
A10 42
A10
A11 43
A11
A12 44
A12
A13 45
A13
A14
46
A14
A15 47
A15
A16 48
A16
A17
49
A17
A18
50
A18
A19 51
A19
A20 52
A20
A21 54
A21
A22 55
A22
A23
56
A23
<01> ( -04C) (
-08B)
( ( -11D) ( 02-09B)
<07> -11B)
Fig. 2.3
II - 3
14
+5V
15
53
14
1 14
17
18
35
57 0V
12
(
BC -04C)
BC
30
FC0 ( -05F)
FC0
29
(
FC1 -05F)
FC1
28
(
FC2 FC2 -05F)
19
+5V
7
(
-04C)
AS AS
10
(
-04C)
R/W R/W
8
(
UDS UDS -04C)
9
(
-04C)
LDS LDS
D0
6
D0
D1
5
D1
D2
4
D2
D3
3
D3
2 D4
D4
68 D5
D5
67
D6
D6
66
D7
D7
65
D8
D8
64
D9
D9
63 D10
D10
62
D11
D11
61
D12
D12
60 D13
D13
59
D14
D14
58 D15
D15
(
<02> -11D)
(
<08> -11B)
( 02-08B)
(
-11D)