Sharp MZ-5600 - Page 76

Keyboard processor (80C49) signal functions
Table 11- 2
Pin No . Signal name
IN/OUT
Description
1
2
TO
XTALt
IN
IN
Data or READY signal input from the System Unit "
;
Accepts a quartz signal16MHz) for the internal clock oscillator.
3
XTAL2 IN
Äccepts a Quartz signal16MHz) for the interna I clock oscillator .
4
RESET
IN
Initialization input of BOC49
5
SS IN
+5V
6
7
INT
EA
IN
IN
CPU interrupt strobe input ISTC)
GND
,
B
RD
- N.C
9
PSEN
- N.C
~
10 WR
-
N.C
11 ALE
-
N.C
12
19
DBO
DB7
IN
Returns signals from the keyboard.
20
Vss
IN
GND
21
P20
OUT Send data to the System Unit lOK)
22
P21
OUT Data enable/start signal (SRK) to CPU
23
P22
OUT Enables data send to the mouse ICTS)
24 P23
-
N.C
25
PROG
- N.C
26
VDD IN +5V
27
30
Pl0
P13
OUT Strobe to the keyboard.
31 P14
OUT CAPS indi.!:ator drive signal
".
32
P15 OUT GRAPH indicator drive signal
33
P16
OUT N.C
34 P17
-
N.C
35
P24
-
N.C
36 .
37 .
38
P25
P26
P27
-
-
-
N.C
N.C
N.C
_.
...
39
Tl IN " Mouse data input (TX 0)
40 Vcc
IN
+5V power supply
~~