HD-15531_02 Datasheet, PDF (4/16 Pages) Intersil Corporation – CMOS Manchester Encoder-Decoder

HD-15531
Pin Description (Continued)
PIN
NUMBER TYPE
NAME
SECTION
DESCRIPTION
14
O DECODER SHIFT
Decoder Output which delivers a frequency (DECODER CLOCK + 1 2), synchronous by
CLOCK
the recovered serial data stream.
15
I TRANSITION SE-
Decoder A high input to this pin causes the transition finder to synchronize on every tran-
LECT
sition of input data. A low input causes the transition finder to synchronize only
on mid-bit transitions.
16
NC
Blank Not connected.
17
O COMMAND SYNC
Decoder Output of a high from this pin occurs during output of decoded data which was
preceded by a Command (or Status) synchronizing character.
18
I DECODER PARITY Decoder An input for parity sense, calling for even parity with input high and odd parity
SELECT
with input low.
19
I DECODER RESET Decoder A high input to this pin during a rising edge of DECODER SHIFT CLOCK resets
the decoder bit counting logic to a condition ready for a new word.
20
I COUNT C0
Both
One of five binary inputs which establish the total bit count to be encoded or de-
coded.
21
GROUND
Both
Supply pin.
22
I MASTER RESET
Both
A high on this pin clears 2:1 counters in both encoder and decoder, and resets
the ÷ 6 circuit.
23
I COUNT C2
Both
See pin 20.
24
O ÷ 6 OUT
Encoder Output from 6:1 divider which is driven by the ENCODER CLOCK.
25
O BIPOLAR ZERO
Encoder An active low output designed to drive the zero or negative sense of a bipolar
OUT
line driver.
26
I OUTPUT INHIBIT
Encoder A low on this pin forces pin 25 and 27 high, the inactive states.
27
O BIPOLAR ONE OUT Encoder An active low output designed to drive the one or positive sense of a bipolar line
driver.
28
I SERIAL DATA IN
Encoder Accepts a serial data stream at a data rate equal to ENCODER SHIFT CLOCK.
29
I ENCODER ENABLE Encoder A high on this pin initiates the encode cycle. (Subject to the preceding cycle be-
ing complete).
30
I SYNC SELECT
Encoder Actuates a Command sync for an input high and Data sync for an input low.
31
I ENCODER PARITY Encoder Sets transmit parity odd for a high input, even for a low input.
SELECT
32
O SEND DATA
Encoder Is an active high output which enables the external source of serial data.
33
I SEND CLOCK IN
Encoder Clock input at a frequency equal to the data rate X2, usually driven by ÷ 6 output.
34
O ENCODER SHIFT
Encoder Output for shifting data into the Encoder. The Encoder samples SDI pin-28 on
CLOCK
the low-to-high transition of ESC.
35
NC
Blank Not connected.
36
I COUNT C3
Both
See pin 20.
37
I ENCODER CLOCK Encoder Input to the 6:1 divider, a frequency equal to 12 times the data rate is usually
input here.
38
O DATA SYNC
Decoder Output of a high from this pin occurs during output of decoded data which was
preceded by a data synchronizing character.
39
I COUNT C4
Both
See pin 20.
40
I COUNT C1
Both
See pill 20.
4