UCCs
MSC8144E Reference Manual, Rev. 3
Freescale Semiconductor
18-19
18.6
UCCs
The QUICC Engine subsystem UCCs implement the Ethernet protocols. This section provides a
general overview of the UCCs. For a detailed description of the feature set and the
protocol-specific programming model, refer to the QUICC Engine™ Block Reference Manual
with Protocol Interworking (QEIWRM). The key features of the UCCs include:
Supports Ethernet and ATM protocols:
— Full 10/100 Mbps, full-duplex/half-duplex Ethernet/IEEE 802.3x/VLAN through
MII/RMII/SMII.
— Full 1000 Mbps, full-duplex Ethernet/IEEE 802.3x/VLAN through RGMII/SGMII.
— Full-duplex ATM AAL5 segmentation and reassembly (SAR) through UTOPIA L2.
UCC clock can be derived from a internal clock or an external signal.
Uses bursts to improve bus usage.
Multibuffer data structure for received and transmitted data.
Buffers and buffer descriptors (BDs) may reside anywhere in system memory.
Programmable size-virtual FIFO buffers.
Echo and local loopback modes for testing.
The UCC block diagram is shown in Figure 18-9.
High-speed protocols require large FIFO depth. Sufficient FIFO size is important for increasing
the QUICC Engine subsystem performance by eliminating overrun and underrun bottlenecks.
Each protocol has an optimized FIFO size that depends not only on the bit rate, but also on other
parameters such as packet or frame size. The UCC, when configured for high-speed protocols,
extends the hardware FIFO into the QUICC Engine subsystem internal RAM. This extension is
called virtual FIFO or VFIFO, because its size and location within the RAM are programmable
according to the specific protocol. The FIFO as shown in Figure 18-9 is constructed using a real
hardware FIFO embedded in the UCC and its extension to a virtual FIFOs in the QUICC Engine
Figure 18-9. UCC Block Diagram
Control and Status
Registers
Clock
Generator
MAC Rx
Control
Unit
MAC Tx
Control
Unit
Receive
Data and
Status FIFO
Transmit
Data and
Status FIFO
L1 Interface (I/O)
CLASS Bus
Serial Bus
TCLK
RCLK
Internal Clocks
L1 Interface (I/O)
Interrupts
**
**
** The size of the FIFO is user-programmable.
Summary of Contents for MSC8144E
Page 1: ...MSC8144E Reference Manual Quad Core Media Signal Processor MSC8144ERM Rev 3 July 2009 ...
Page 48: ...MSC8144E Reference Manual Rev 3 xlviii Freescale Semiconductor ...
Page 86: ...MSC8144E Reference Manual Rev 3 1 38 Freescale Semiconductor Overview ...
Page 168: ...MSC8144E Reference Manual Rev 3 3 60 Freescale Semiconductor External Signals ...
Page 242: ...MSC8144E Reference Manual Rev 3 5 26 Freescale Semiconductor Reset ...
Page 314: ...MSC8144E Reference Manual Rev 3 8 24 Freescale Semiconductor General Configuration Registers ...
Page 414: ...MSC8144E Reference Manual Rev 3 10 14 Freescale Semiconductor MSC8144E SC3400 DSP Subsystem ...
Page 452: ...MSC8144E Reference Manual Rev 3 11 38 Freescale Semiconductor Internal Memory Subsystem ...
Page 520: ...MSC8144E Reference Manual Rev 3 12 68 Freescale Semiconductor DDR SDRAM Memory Controller ...
Page 1070: ...MSC8144E Reference Manual Rev 3 21 28 Freescale Semiconductor Timers ...