scn68652 NXP Semiconductors, scn68652 Datasheet - Page 5

• Manufacturer Part Number: scn68652
• Description: Multi-protocol Communications Controller Mpcc
• Manufacturer: NXP Semiconductors

*H = High byte – bits 15–8
Philips Semiconductors
Table 1.
NOTES:
Table 2.
1995 May 01
L = Low byte – bits 7–0
FCS
BCC
CHARACTER
Multi-protocol communications controller (MPCC)
Addressable
PCSAR
PCR
RDSR
TDSR
Non-Addressable
CCSR
HSR
RxSR
TxSR
RxCRC
TxCRC
Register Access
Error Control
Frame check sequence is transmitted/received
as 16 bits following the last data character of a
BOP message. The divisor is usually
CRC–CCITT (X
preset to 1’s but can be other wise determined
by ECM. The inverted remainder is transmitter as
the FCS.
Block check character is transmitted/received as
two successive characters following the last data
character of a BCP message. The polynomial is
CRC–16 (X
with dividend preset to 0’s (as specified by
ECM). The true remainder is transmitted as the
BCC.
REGISTERS
Parameter control sync/
address register
Parameter control register
Receive data/status register
Transmit data/status register
Control character shift register
Holding shift register
Receiver shift register
Transmitter shift register
Receiver CRC accumulation
register
Transmitter CRC generation
register
NOTE:
Refer to Register Formats for mnemonics and description.
16
PCSAR
PCR
RDSR
TDSR
+ X
16
DESCRIPTION
15
+ X
+ X
RERR
TERR
12
APA
15
15
15
15
2
+ X
+ 1) or CRC–CCITT
5
14
14
+ 1) with dividend
PROTO
NOT DEFINED
TxCL
Figure 3. Short Form Register Bit Formats
14
14
A B C
13
13
13
SS/GA
13
12
12
NO. OF BITS
T x
ROR
TGA
SAM
11
11
12
12
C L
16
16
16
16
16
16
E
8
8
8
8
R x
TABORT
IDLE
RAB/
11
11
GA
C L
5
10
10
E
1. ( ) = contents of.
2. For IDLE = 0 or 1 respectively.
Table 3.
NOTES:
10
10
BOP
FLAG
ABORT
GA
Address
BCP
SYNC
OPERATION
REOM
TEOM
9
9
E C M
RxCL
9
9
PCSAR
receiver and transmitter. PCSAR
SYNC character (BCP) or secondary station address (BOP).
RDSR
RDSR
TDSR
information. TDSRL = TxDB contains the character to be
transmitted
These registers are used for character assembly (CSSR
These registers are used for character assembly (CSSR,
HSR, RxSR), disassembly (TxSR), and CRC
accumulation/generation (RxCRC, TxCRC).
RSOM
TSOM
8
8
8
8
,
H
H
L
H
= RxDB contains the received assembled character.
contains transmitter command and status
Special Characters
contains receiver status information.
7 6
and PCR contain parameters common to the
01111110
11111111 generation
01111111 detection
01111111
(PCSAR
(PCSAR
(TxDB)
),
BIT PATTERN
5 4 3 2 1 0
S/AR
RxDB
TxDB
2
L
L
generation
)
) or
1
SCN2652/SCN68652
SD00059
DESCRIPTION*
y (
L
Frame message
Terminate communication
Terminate loop mode
repeater function
Secondary station address
Character synchronization
),
contains a programmable
FUNCTION
Product specification