Epson FX-80 Technical Service Data page 15

SAFETY PRECAUTIONS
1.
Use an
isolation
transformer
for
servicing.
2.
Maintain
AC
line voltage
at
rated
input.
3.
Remove
AC
power from
the
printer before servicing or
installing electrostatically sensitive
devices.
Examples
of typical
ES
devices are integrated
circuits
and semiconductor
"chip"
components.
4.
Use extreme
caution
when
handling
the printed
circuit
boards.
Some
semiconductor
devices can be
damaged
easily
by
static
electricity.
Drain
off
any
electrostatic charge on your body
by touching
a
known
earth ground.
Wear
a
commercially
available
discharging
wrist strap device. This should be removed
prior to applying
power
to
the
unit
under
test.
5.
Use
a grounded-tip, low
voltage soldering
iron.
6.
Use
an
isolation (times
10)
probe on scope.
7.
Do
not
remove
or
install
boards, mechanical
or
electrical parts, or other peripherals with
printer
AC
power On.
8.
Do
not use
freon-propelled sprays. These can
generate
electrical
charges
sufficient to
damage
semiconductor
devices.
9.
This printer
is
equipped
with
a grounded
three-pronged
AC
plug. This plug
must
fit
into
a
grounded
AC
power
outlet.
Do
not
defeat the
AC
plug safety
feature.
10.
Periodically
examine
the
AC
power
cord
for
damaged
or
cracked
insulation.
11.
The
printer cabinet
is
equipped
with vents
to
prevent heat
build-up. Never
block, cover, or obstruct these
vents.
12.
Instructions should be
given,
especially to children, that objects should
not be
dropped
or
pushed
into the vents
of the cabinet.
This could cause shock
or
equipment damage.
13.
Never expose
the
printer to water.
If
exposed
to
water
turn the unit
Off.
Do
not place the
printer
near possible water sources.
14.
Never
leave the printer unattended
or
plugged
into
the
AC
outlet for long periods of time.
Remove
AC
plug
from
AC
outlet dur-
ing lightning storms.
15.
Do
not allow anything
to rest
on
AC
power
cord.
16.
Unplug
AC
power
cord from
outlet before cleaning
printer.
17.
Never use
liquids or aerosols
directly
on
the
printer.
Spray on
cloth
and
then apply
to
the
printer cabinet.
Make
sure the
printer
is
disconnected from
the
AC
power
line.
LINE DEFINITIONS
A0ThruA13
Address
Lines P/S
Parallel/Serial
AC2
Thru
AC7
RO
Read
ACK
Acknowledge
RDY
,
Ready
BDO
Thru
BD7
Data Lines
RST
Reset
CA6
SEL
Select
CA7
SEL
IN
Select Input
CD1 ThruCD7
Control Data Lines
SEL OUT
Select
Output
CSO Thru
CS7
Chip Select
TC
DO
Thru D7
Data Lines
TXD
PET/TRS
Select
DC20
Thru
DC22
UDO
Thru
UD7
Data Lines
DC24
Thru
DC27
WR
Write
ERR
Error
1
Line
Identification
INST
Initialize 2 Line
Identification
INT1
Interrupt 3
Line Identification
PDO
Thru
PD7
Data Lines 4
:
Line
Identification
PE Paper Empty
5
Line Identification
Any
Bar above any alphabetical or numerical combination
indicates
line active
in
a low
(0)
state.