peb20534 Infineon Technologies Corporation, peb20534 Datasheet - Page 198

• Manufacturer Part Number: peb20534
• Description: Dma Supported Serial Communication Controller With 4 Channels
• Manufacturer: Infineon Technologies Corporation

8.3
8.3.1
Character oriented protocols achieve synchronization between transmitting and
receiving station by means of special SYN characters. Two examples are the
MONOSYNC and IBM’s BISYNC procedures. BISYNC has two starting SYN characters
while MONOSYNC uses only one SYN. Figure 74 gives an example of the message
format.
Figure 74
The SYN character, its length, the length of data characters and additional parity
generation are programmable:
• 1 SYN character with 6 or 8 bit length (MONOSYNC), programmable via register
• 2 SYN characters with 6 or 8 bit length each (BISYNC), programmable via registers
• Data character length may vary from 5 to 8 bits (bit field ’CHL’ in register CCR2).
• Parity information (even/odd parity, mark, space) may be appended to the character
8.3.2
The receiver is generally activated by setting bit ’RAC’ in register CCR2. Additionally, the
CD signal may be used to control data reception depending on the selected clock mode.
After issuing the HUNT command, the receiver monitors the incoming data stream for
the presence of specified SYN character(s). However, data reception is still disabled. If
synchronization is gained by detecting the SYN character(s), an SCD interrupt is
generated and all following data is pushed to the receive FIFO, i.e. control sequences,
data characters and optional CRC frame checking sequence (the LSB is received first).
Data Sheet
SYNCR.
SYNCR.
(bit ’PARE’ and bit field ’PAR’ in register CCR2).
(SYNL)
2 Leading
SYN
Characters
SYN
Character Oriented Synchronous (BISYNC) Protocol Mode
Character Framing
Data Reception
BISYNC Message Format
(SYNH)
SYN
Start
of
Header
SOH
Header
Start
of
Text
198
STX
Text
Detailed Protocol Description
(Data)
End
of
Text
ETX
Frame
Checking
Sequence
PEB 20534
PEF 20534
CRC
2000-05-30
ITD01805