Service manual
4-1.
Memory
map
The MZ-800 has a different
memory
map depending on
o MZ-800
memory
map
FFFF"
EOOO
0000
COOO
AOOO
01000
--
4000
2000
1000
MAIN
o-RAM
64K.
O-RAM
MZ-700
mode
r---,
~
~
ROM
~
~
VRAM
MZ-800
mode
MAIN
o-RAM
64 KB
O-RAM
MZ-800
the mode. To have
compatibility
with
the MZ-700, it has
two
modes
of
the MZ-700
mode
and MZ-800 mode.
O
[J
D
OVOR"';:
__
,
I I I I
: :
In:
lml:
~
__
J L
__
J
,.--,
1 I
1 I
: IIV) I
1 I
1 I
L
__
oJ
~
640
)(
200
mode
VRAM
320 x 200
mode
NOTE:
r--..,
1 1
:
eX):
1 1
,-
__
.J
Item within
dotted
lin.
represents
an
option
unit
MZ·1R25
Memory
map
changes
after
initial
program
loading
$0000
SI
000
$2000
$8000
SEooo
SFFFF
® Power on (resel)
MZ-800
mode
MON. ROM
CG.ROM
DRAM
V-RAM
(320x2oo
mode)
DRAM
MON. ROM
@
At
start
of
monitor
MZ-700
mode
$0000
r------,
MON.
ROM
$1000
r-----;
LD
A, 08H
OUT (CE),
A
=>
DRAM
SDOOO
V-RAM
SEooo
SE010
I<.!'Y.
nM~K
MON. ROM
SFFFF
•
Memory
map at
power
on is in the MZ-800
mode
as
in
®,
but
it
changes
to
the MZ-700
mode
by the
monitor
ROM
when
the
monitor
program
starts.
After
transferring the
CG
data
to
the
VRAM
PCG
area
from
the
CG
ROM at @, the
memory
map
then returns
to
®.
• When the system
program
is completed
to
load,
the
memory
map goes
into
the MZ-700
mode
if
the
system switch (SW1) is set
to
ON side.
If
set
to
OFF
side,
it
changes
to
the MZ-800 mode, then the
memory
map
as
in @. During those changes, all
memory
spaces are composed
of
RAM and isolated
from
ROM and VRAM.
IN
(EOH),
A
=>
©
Wril.
10
PeG
from
CG
MZ-7oo
mode
$0000
$1000
$2000
MON. ROM
CG.ROM
D-RAM
@ System operation
MZ-7oo & 800 modes
$0000
D-RAM
IN
(El
H), A
~
6
SCOOO
V-RAM (CG)
SDOOO
SEooo
V-RAM
SE010
MON. ROM
SFFFF
SFFFF
L...
___
---'
• Depression
of
the manual reset switch assumes
memory
map transition in order
of
®
~
®
~
@
~
®,
similar
as in the case
of
power
on.
• However, depression
of
the reset switch in conjunc-
tion
with
the I CTRL I key assumes the
memory
map
of
@ after being changed once
to
the
MZ-700
or
MZ-800
mode
depending on the state
of
the system switch.
In
the case
of
the
MZ-800 mode,
it
is set
to
the plane I.
IT
(4-color mode)
of
the
320 x 200 mode.