Epson PX-8 - Page 285

REV.-A
Pin No.
Signal Name
In/Out Function
13
AB4 In Address bus 4
14
AB15 In Address bus 1 5
15
AB3 In Address bus 3
16
DRAO Out DRAM address 0(8)
--
17
RAS1 Out
Low address stroke: RAS signal to RAS.
18
W1
Out
Write enable: WE signal to DRAM.
19
AB2 In Address bus 2
20 AB1
In Address bus 1
21
ABO
In Address bus 0
22
N/C
-
Not used
23
N/C
-
Not used
24
N/C
-
Not used
-
25 RD
In Read signal
26 CSROM
Out IPL
ROM chip select signal
-
27
MR Out Memory read signal
--
28
Z-INT
Out Interrupt request signal
to main CPU
--
29 Z-RF
In Refresh signal from main CPU
30 VC - Circuit voltage (+5V)
--
31
HLTA In Halt signal
-
32
M1 In Indicates that main CPU is in machine cycle
1 (opcode fetch)
--
33
MRQ
In
Memory request signal
--
34 RSO Out System reset signal resets the whole ma-
chine.
35 DRA3
Out DRAM address 3 (11)
36
N/C
-
Not used
37
N/C
-
Not used
38 DRA 7 Out DRAM address 7 (15)
39
N/C
-
Not used
7-14