Instruction Manual

DS33R11 Ethernet Mapper with Integrated T1/E1/J1 Transceiver
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4 ACRONYMS AND GLOSSARY
• BERT: Bit Error-Rate Tester
• DCE: Data Communication Interface
• DTE: Data Terminating Interface
• FCS: Frame Check Sequence
• HDLC: High-Level Data Link Control
• MAC: Media Access Control
• MII: Media Independent Interface
• RMII: Reduced Media Independent Interface
• WAN: Wide Area Network
Note 1: Previous versions of this document used the term “Subscriber” to refer to the Ethernet Interface function.
The register names have been allowed to remain with a “SU.” prefix to avoid register renaming.
Note 2: Previous versions of this document used the term “Line” to refer to the Serial Interface. The register names
have been allowed to remain with a “LI.” prefix to avoid register renaming.
Note 3: The terms “Transmit Queue” and “Receive Queue” are with respect to the Ethernet Interface. The Receive
Queue is the queue for the data that arrives on the MII/RMII interface, is processed by the MAC and stored in the
SDRAM. Transmit queue is for data that arrives from the Serial port, is processed by the HDLC and stored in the
SDRAM to be sent to the MAC transmitter.
Note 4: This data sheet assumes a particular nomenclature of the T1 operating environment. In each 125μs frame
there are 24 8-bit channels plus a framing bit. It is assumed that the framing bit is sent first followed by channel 1.
Each channel is made up of eight bits that are numbered 1 to 8. Bit number 1 is the MSB and is transmitted first.
Bit number 8 is the LSB and is transmitted last. The term “locked” is used to refer to two clock signals that are
phase- or frequency-locked or derived from a common clock (i.e., a 1.544MHz clock can be locked to a 2.048MHz
clock if they share the same 8kHz component). Throughout this data sheet, the following abbreviations are used:
B8ZS Bipolar with 8 Zero Substitution
BOC Bit-Oriented Code
CRC Cyclical Redundancy Check
D4 Superframe (12 frames per multiframe) Multiframe Structure
ESF Extended Superframe (24 frames per multiframe) Multiframe Structure
FDL Facility Data Link
FPS Framing Pattern Sequence in ESF
Fs Signaling Framing Pattern in D4
Ft Terminal Framing Pattern in D4
HDLC High-Level Data Link Control
MF Multiframe
SLC–96 Subscriber Loop Carrier—96 Channels