Heathkit H9 - TTL Serial Input;Output

Page
14
TTL
Connections
]-l
77
rc60r
-------_lr
t
120
:"*-H
@
rc 6t2
r/0
ctRcutT
BOARD
PICIORIAL
2.7
TTL
Serial Input/Output
Pictorial
2-7
shows
the
iumper
wires
necessary
for
the
TTL
configuration.
The TTL
inputs
are
standard TTL
logic
levels
as shown
in Pictorial
2-8.
A mark
is de-
fined
as a logic 1
and a
space is
defined as a logic
0.
TTL INPU]
LEVELS
+5
t) A
+.4
0
TTL OUTPUT
LEVTLS
PICTORIAL
2.8
Pictorial
2-9
shows
the partial
schematic
of the TTL
wiring
on
the I/O
circuit
board.
The
jumper
wire
that
disables
the
reader
control
is
shown
in
pictorials
2-7
and
2-9.
Refer
to "Reader
Control"
on Page
18.
E-(\c
oeoirs
I
iL
Vi
-
icers
I
MARK
(LOGIC
1)
S
PACE
(LOG
I C O)
MARK
(LOG
IC I)
PACI {LOGIC
())