Spectravideo MKI, Сервисное – Техническое руководство

Страница: 12 / 134

PIN:
NAME:
45
0
46
0
47
0
48 0
49-50
GND
DESCRIPTION:
Buffered
MEMORY BANK CONTROL signal.
Pulling
this
signal LOW enables the b
a n
k
32 por ti on
of the memory
(32K, Addr.-- 8000H-FFFFH),
and
disables the
user RAM on board through
the
sig nal .
Buffered
MEMORY BANK CONTROL signal.
Pulling th is
signal LOW enables the b
a
n k 31 por tion
of t he memory
(32K, Addr,-- OOOOH-7FFFH),
and
disa bles the
BASH-: ROH on board through
the
signal.
Buffered
MEMORY BANK CONTROL signal.
Pulling
this
signal LOW enables the ba
n
k 22 por tion
of the memory
(32K, Addr.--8000H-FFFFH)
and
disables t he
usser RAH on board through
the
RA DIS
s
i
gna
l
.
Buffered
MEMORY BANK CONTROL signal.
Pulling
this
signal LOW enables
t
he
bank 21
portion
of
the memory
(32K, Addr.-- OOOOH-7FFFFH)
whi ch
is
t he
lower
portion of
SVI328 user
a
ddre
ss
a
b
l
e
memory, and
disables the BASIC ROM
on board .
System el
e
ctrical ground.
2 . 7