INTEGRATED CIRCUITS
SCN68562
Dual universal serial communications
controller (DUSCC)
Product specification
IC19 Data Handbook
1995 May 01
Philips
Semiconductors
Philips Semiconductors
Product specification
Dual universal serial communications controller (DUSCC)
SCN68562
DESCRIPTION
The Philips Semiconductors SCN68562 Dual Universal Serial
Communications Controller (DUSCC) is a single-chip MOS-LSI
communications device that provides two independent,
multi-protocol, full-duplex receiver/transmitter channels in a single
package. It supports bit-oriented and character-oriented (byte count
and byte control) synchronous data link controls as well as
asynchronous protocols. The SCN68562 interfaces to the 68000
MPUs via asynchronous bus control signals and is capable of
program-polled, interrupt driven, block-move or DMA data transfers.
The operating mode and data format of each channel can be
programmed independently.
Each channel consists of a receiver, a transmitter, a 16-bit
multifunction counter/timer, a digital phase-locked loop (DPLL), a
parity/CRC generator and checker, and associated control circuits.
The two channels share a common bit rate generator (BRG),
operating directly from a crystal or an external clock, which provides
16 common bit rates simultaneously. The operating rate for the
receiver and transmitter of each channel can be independently
selected from the BRG, the DPLL, the counter/timer, or from an
external 1X or 16X clock, making the DUSCC well suited for
dual-speed channel applications. Data rates up to 4Mbits per
second are supported.
The transmitter and receiver each contain a four-deep FIFO with
appended transmitter command and receiver status bits and a shift
register. This permits reading and writing of up to four characters at
a time, minimizing the potential of receiver overrun or transmitter
underrun, and reducing interrupt or DMA overhead. In addition, a
flow control capability is provided to disable a remote transmitter
when the FIFO of the local receiving device is full.
Two modem control inputs (DCD and CTS) and three modem
control outputs are provided. These inputs and outputs can be
optionally programmed for other functions.
FEATURES
General Features
transmitter
•
Dual full-duplex synchronous/asynchronous receiver and
•
Multiprotocol operation
–
BOP: HDLC/ADCCP, SDLC, SDLC loop, X.25 or X.75 link level,
etc.
–
COP: BISYNC, DDCMP
–
ASYNC: 5–8 bits plus optional parity
•
Four character receiver and transmitter FIFOs
A PACKAGE
7
8
1
47
46
PIN CONFIGURATIONS
N PACKAGE
IACKN
A3
A2
A1
RTxDAKBN/
GPI1BN
IRQN
RESETN
RTSBN/
SYNOUTBN
TRxCB
1
2
3
4
5
6
7
8
9
48 V
DD
47
46
45
44
43
42
41
40
39
DIP
38
37
36
35
34
33
32
31
30
29
28
27
26
25
A4
A5
A6
RTxDAKAN/
GPI1AN
X1/CLK
X2/IDCN
RTSAN/
SYNOUTAN
TRxCA
RTxCA
DCDAN/
SYNIAN
Rxda
TxDA
TxDAKAN/
GPI2AN
RTxDRQAN/
GPO1AN
TxDRQAN/
GPO2AN/RTSAN
CTSAN/LCAN
D0
D1
D2
D3
DONEN
R/WN
CSN
20
21
Pin Function
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
34
33
TOP VIEW
Pin Function
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
CSN
R/WN
DONEN
D3
D2
D1
D0
NC
CTSAN/LCAN
TxDRQAN/
GPO2AN/RTSAN
RTxDRQAN/
GPO1AN
TxDAKAN/
GPI2AN
TxDA
RxDA
NC
DCDAN/
SYNIAN
RTxCA
TRxCA
RTSAN/
SYNOUTAN
X2/IDCN
X1/CLK
RTxDAKAN/
GPI1AN
A6
A5
A4
V
DD
PLCC
INDEX
CORNER
RTxCB 10
DCDBN/ 11
SYNIBN
RxDB 12
TxDB 13
TxDAKBN/
GPI2BN
RTxDRQBN/
GPO1BN
TxDRQBN/
GPO2BN/RTSBN
CTSBN/LCBN
14
15
16
17
D7 18
D6 19
D5 20
D4 21
DTACKN 22
DTCN 23
GND 24
IACKN
A3
A2
A1
RTxDAKBN/
GPI1BN
IRQN
NC
RESETN
RTSBN/
SYNOUTBN
TRxCB
RTxCB
DCDBN/
SYNIBN
NC
RxDB
TxDB
TxDAKBN/
GPI2BN
RTxDRQBN/
GPO1BN
TxDRQBN/
GPO2BN/RTSBN
CTSBN/LCBN
D7
D6
D5
D4
DTACKN
DTCN
GND
SD00222
Figure 1. Pin Configurations
1995 May 01
2
853-0831 15179
Philips Semiconductors
Product specification
Dual universal serial communications controller (DUSCC)
SCN68562
•
0 to 4MHz data rate
•
Programmable bit rate for each receiver and transmitter selectable
from:
–
16 fixed rates: 50 to 38.4k baud
–
One user-defined rate derived from programmable
counter/timer
–
External 1X or 16X clock
–
Digital phase-locked loop
•
Break generation with handshake for counting break characters
•
Detection of start and end of received break
•
Character compare with optional interrupt on match
•
Transmits up to 4Mbs and receive up to 2Mbps data rates
Character-Oriented Protocol Features
•
Parity and FCS (frame check sequence LRC or CRC) generation
and checking
•
Programmable data encoding/decoding: NRZ, NRZI, FM0, FM1,
Manchester
•
Programmable channel mode: full- and half-duplex, auto-echo, or
local loopback
•
Programmable data transfer mode: polled, interrupt, DMA, wait
•
DMA interface
–
Compatible with the Philips Semiconductors SCB68430 Direct
Memory Access Interface (DMAI) and other DMA controllers
–
Single- or dual-address dual transfers
–
Half- or full-duplex operation
–
Automatic frame termination on counter/timer terminal count or
DMA DONE
•
Character length: 5 to 8 bits
•
Odd or even parity, no parity, or force parity
•
LRC or CRC generation and checking
•
Optional opening PAD transmission
•
One or two SYN characters
•
External sync capability
•
SYN detection and optional stripping
•
SYN or MARK line-fill on underrun
•
Idle in MARK or SYNs
•
Parity, FCS, overrun, and underrun error detection
BISYNC Features
–
EBCDIC or ASCII header, text and control messages
–
SYN, DLE stripping
–
EOM (end of message) detection and transmission
–
Auto transparent mode switching
–
Auto hunt after receipt of EOM sequence (with closing PAD
check after EOT or NAK)
–
Control character sequence detection for both transparent and
normal text
•
Interrupt capabilities
–
Daisy chain option
–
Vector output (fixed or modified by status)
–
Programmable internal priorities
–
Maskable interrupt conditions
•
Multi-function programmable 16-bit counter/timer
–
Bit rate generator
–
Event counter
–
Count received or transmitted characters
–
Delay generator
–
Automatic bit length measurement
Bit-Oriented Protocol Features
•
Modem controls
–
RTS, CTS, DCD, and up to four general I/O pins per channel
–
CTS and DCD programmable autoenables for Tx and Rx
–
Programmable interrupt on change of CTS or DCD
•
Character length: 5 to 8 bits
•
Detection and transmission of residual character: 0–7 bits
•
Automatic switch to programmed character length for 1 field
•
Zero insertion and deletion
•
Optional opening PAD transmission
•
Detection and generation of FLAG, ABORT, and IDLE bit patterns
•
Detection and generation of shared (single) FLAG between
frames
•
On-chip oscillator for crystal
•
TTL compatible
•
Single +5V power supply
Asynchronous Mode Features
•
Character length: 5 to 8 bits
•
Odd or even parity, no parity, or force parity
•
Up to two stop bits programmable in 1/16-bit increments
•
1X or 16X Rx and Tx clock factors
•
Parity, overrun, and framing error detection
•
False start bit detection
•
Start bit search 1/2-bit time after framing error detection
1995 May 01
3
•
Detection of overlapping (shared zero) FLAGs
•
ABORT, ABORT-FLAGs, or FCS FLAGs line-fill on underrun
•
Idle in MARK or FLAGs
•
Secondary address recognition including group and global
address
•
Single- or dual-octet secondary address
•
Extended address and control fields
•
Short frame rejection for receiver
•
Detection and notification of received end of message
•
CRC generation and checking
•
SDLC loop mode capability
Philips Semiconductors
Product specification
Dual universal serial communications controller (DUSCC)
SCN68562
ORDERING INFORMATION
DESCRIPTION
48-Pin Plastic Dual In-Line Package (DIP)
52-Pin Plastic Leaded Chip Carrier (PLCC) Package
V
CC
= +5V +5%, T
A
= 0°C to +70°C
Serial Data Rate = 4Mbps Maximum
SCN68562C4N48
SCN68562C4A52
DWG #
SOT240-1
SOT238-3
NOTE: See SCN26562/SCN68562 User’s Guide for detailed description of all the features.
BLOCK DIAGRAM
D0-D7
BUS
BUFFER
CHANNEL MODE
AND TIMING A/B
DPLL CLK
MUX A/B
INTERFACE/
OPERATION
CONTROL
ADDRESS
DECODE
DTACKN
RWN
A1-A6
CSN
RESETN
MPU
INTERFACE
COUNTER/
TIMER A/B
R/W
DECODE
DMA
CONTROL
CCRA/B
RTxDRQAN/GPO1AN
RTxDRQBN/GPO1BN
TxDRQAN/GPO2AN
TxDRQBN/GPO2BN
RTxDAKAN/GPI1AN
RTxDAKBN/GPI1BN
TxDAKAN/GPI2AN
TxDAKBN/GPI2BN
DTCN
DONEN
PCRA/B
RSRA/B
TRSRA/B
ICTSRA/B
DMA INTERFACE
GSR
CMR1A/B
CMR2A/B
OMRA/B
INTERNAL BUS
C/T CLK
MUX A/B
CTCRA/B
CTPRHA/B
CTPRLA/B
CTHA/B
CTLA/B
DPLL A/B
BRG
TRANSMIT A/B
TRANS CLK
MUX
TPRA/B
TTRA/B
TX SHIFT
REG
TRANSMIT
4 DEEP
FIFO
TxD A/B
TRxCA/B
RTxCA/B
RTSBN/SYNOUTBN
RTSAN/SYNOUTAN
CTSA/BN
DCDBN/SYNIBN
DCDAN/SYNIAN
SPECIAL
FUNCTION
PINS
CONTROL
CRC
GEN
SPEC CHAR
GEN LOGIC
RECEIVER A/B
RCVR CLK
MUX
INTERRRUPT
CONTROL
ICRA/B
IRQN
IERA/B
IACKN
IVR
IVRM
DUSCC
LOGIC
RPRA/B
RTRA/B
S1RA/B
S2RA/B
RxD A/B
RCVR
SHIFT REG
RECEIVER
4 DEEP
FIFO
CRC
ACCUM
BISYNC
COMPARE
LOGIC
X1/CLK
X2/IDCN
OSCILLATOR
SD00223
Figure 2. Block Diagram
1995 May 01
4
Philips Semiconductors
Product specification
Dual universal serial communications controller (DUSCC)
SCN68562
PIN DESCRIPTION
In this data sheet, signals are discussed using the terms ‘active’ and ‘inactive’ or ‘asserted’ and ‘negated’ independent of whether the signal is
active in the High (logic 1) or Low (logic 0) state. N at the end of a pin name signifies the signal associated with the pin is active-Low (see
individual pin description for the definition of the active level of each signal.) Pins which are provided for both channels are designated by A/B
after the name of the pin and the active-Low state indicator, N, if applicable. A similar method is used for registers provided for both channels:
these are designated by either an underline or by A/B after the name.
MNEMONIC
A1 – A6
D0 – D7
DIP
PIN NO.
4-2,
45-47
31-28,
21-18
TYPE
I
I/O
NAME AND FUNCTION
Address Lines:
Active-High. Address inputs which specify which of the internal registers
is accessed for read/write operation.
Bidirectional Data Bus:
Active High, 3-State. Bit 0 is the LSB and bit 7 is the MSB. All
data, command, and status transfers between the CPU and the DUSCC take place over
this bus. The data bus is enabled when CSN is Low, during interrupt acknowledge cycles
and single-address DMA acknowledge cycles.
Read/Write:
A High input indicates a read cycle and a Low input indicates a write cycle
when a cycle is initiated by assertion of the CSN input.
Chip Select:
Active-Low input. When Low, data transfers between the CPU and the
DUSCC are enabled on D0 – D7 as controlled by the R/WN and A1 – A6 inputs. When
CSN is High, the DUSCC is isolated from the data bus (except during interrupt
acknowledge cycles and single-address DMA transfers) and D0 – D7 are placed in the
3-State condition.
Data Transfer Acknowledge:
Active-Low, 3-State. DTACKN is asserted on a write cycle
to indicate that the data on the bus has been latched, and on a read cycle or interrupt
acknowledge cycle to indicate valid data is on the bus. The signal is negated when
completion of the cycle is indicated by negation of the CSN or IACKN input, and returns to
the inactive state (3-State) a short period after it is negated. In a single address DMA
mode, data is latched with the falling edge of DTCN. DTACKN is negated when
completion of the cycle is indicated by the assertion of DTCN or negation of DMA
acknowledge inputs (whichever occurs first), and returns to the inactive state (3-State) a
short period after it is negated. When negated, DTACKN becomes an open-drain output
and requires an external pull-up resistor.
Interrupt Request:
Active-Low, open-drain. This output is asserted upon occurrence of
any enabled interrupting condition. The CPU can read the general status register to
determine the interrupting condition(s), or can respond with an interrupt acknowledge cycle
to cause the DUSCC to output an interrupt vector on the data bus.
Interrupt Acknowledge:
Active-Low. When IACKN is asserted, the DUSCC responds by
placing the contents of the interrupt vector register (modified or unmodified by status) on
the data bus and asserting DTACKN. If no active interrupt is pending, DTACKN is not
asserted.
Crystal or External Clock:
When using the crystal oscillator, the crystal is connected
between pins X1 and X2. If a crystal is not used, and external clock is supplied at this
input. This clock is used to drive the internal bit rate generator, as an optional input to the
counter/timer or DPLL, and to provide other required clocking signals.
Crystal or Interrupt Daisy Chain:
When a crystal is used as the timing source, the
crystal is connected between pins X1 and X2. This pin can be programmed to provide and
interrupt daisy chain active-Low output which propagates the IACKN signal to lower priority
devices, if no active interrupt is pending. This pin should be grounded when an external
clock is used on X1 and X2, is not used as an interrupt daisy chain output.
Master Reset:
Active-Low. A low on this pin resets the transmitters and receivers and
resets the registers shown in Table 1 of the CDUSCC Users’ Guide. Reset in
asynchronous, i.e., no clock is required.
Channel A (B) Receiver Serial Data Input:
The least significant bit is received first. If
external receiver clock is specified for the channel, the input is sampled on the rising edge
of the clock.
Channel A (B) Transmitter Serial Data Output:
The least significant bit is transmitted
first. This output is held in the marking (High) condition when the transmitter is disabled or
when the channel is operating in local loopback mode. If external transmitter clock is
specified for the channel, the data is shifted on the falling edge of the clock.
Channel A (B) Receiver/Transmitter Clock:
As an input, it can be programmed to
supply the receiver, transmitter, counter/timer, or DPLL clock. As an output, can supply the
counter/timer output, the transmitter shift clock (1X), or the receiver sampling clock (1X).
The maximum external receiver/transmitter clock frequency is 4MHz.
R/WN
CSN
26
25
I
I
DTACKN
22
O
IRQN
6
O
IACKN
1
I
X1/CLK
43
I
X2/IDCN
42
O
RESETN
7
I
RxDA, RxDB
37, 12
I
TxDA, TxDB
36, 13
O
RTxCA, RTxCB
39, 10
I/O
1995 May 01
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