stlc1510 STMicroelectronics, stlc1510 Datasheet - Page 15

• Manufacturer Part Number: stlc1510
• Description: Northenlite G.lite Dmt Transceiver
• Manufacturer: STMicroelectronics

5.4.2 Mapper Description
The mapper realizes the bit extraction and constella-
tion encoding functions specified in G.922.2 (§ 7.8.1
and § 7.8.2 respectively); it is mainly intended to ac-
celerate the main CPU in these bit manipulation op-
erations.
The mapper consists of:
5.4.3 Demapper Description
The demapper consists of:
Figure 4. EPM and LAMBA Bus Block Diagram
A Bit Unpack unit, extracting a variable length
bit string from the frame RAM
A Constellation Encoder, converting the bits to
a constellation point
Pseudo -random sequence generators PRBS,
& MAPPRG.
A Constellation Decoder, converting the input
constellation point to bits.
A Bit Pack unit, inserting the variable length bit
string into the frame RAM.
EMU
ARM7
CORE
E P M
TAP
ASB can ex tend to the APB,
X Bus , Y Bus, P Bus and
LAM BA Bus .
X Bus can extend to LAMB A
Bus.
B oot
R OM
Cntl
Int
A PB
ASB
Tmr
M em
B ridg e
APB
D ec
Off Chip
H PI
I/F
Bridge /
Arbiter/
Dec od e
DPCO MM
5.5 Embedded Processor Core - Functional
The Embedded Processor Core consists of two pro-
grammable cores; the ARM7TDMI 32-bit micropro-
cessor and the D950 16-bit DSP, their associated
peripherals/memory, a DPCOMM (Dual-Port Com-
munications) for messaging, and a Bridge/Arbiter/
Decode (BAD) block. A block diagram of the EPM is
shown below.
There are two buses locally used by the ARM7 core
which are collectively known as the Advanced Micro-
controller Bus Architecture (AMBA):
The LAMBA Bus, a subset of the AMBA bus specifi-
cation, connects all the blocks in the data pump por-
tion of the STLC1510.
Advanced System Bus (ASB)
Advanced Peripheral Bus (APB) connected to
the ASB via an APB Bridge
Description
Xm em
Ym em
Pm em
X BUS
Y BUS
P BUS
LA MBA BUS
16
C trl
Int
T mr
D ec
D ec
EM U
D950
CORE
STLC1510
TAP
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