MOD5234-100IR NetBurner Inc, MOD5234-100IR Datasheet - Page 107

• Manufacturer Part Number: MOD5234-100IR
• Description: MOD5234 10/100 ETHERNET MODULE
• Manufacturer: NetBurner Inc
• Type: Controllers & Processorsr

Specifications of MOD5234-100IR

• Interface: I²C, SPI, UART
• Voltage - Supply: 2.5V
• Mounting Type: Surface Mount
• Package / Case: Module
• Product: Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Data Format: -
• Baud Rates: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: Q4483564

Chapter 4
Enhanced Multiply-Accumulate Unit (EMAC)
This chapter describes the functionality, microarchitecture, and performance of the enhanced
multiply-accumulate (EMAC) unit in the ColdFire family of processors.
4.1
The MAC design provides a set of DSP operations which can be used to improve the performance
of embedded code while supporting the integer multiply instructions of the baseline ColdFire
architecture.
The MAC provides functionality in three related areas:
The ColdFire family supports two MAC implementations with different performance levels and
capabilities. The original MAC uses a three-stage execution pipeline optimized for 16-bit
operands and featuring a 16x16 multiply array with a single 32-bit accumulator. The EMAC
features a four-stage pipeline optimized for 32-bit operands, with a fully pipelined 32 × 32
multiply array and four 48-bit accumulators.
The first ColdFire MAC supported signed and unsigned integer operands and was optimized for
16x16 operations, such as those found in a variety of applications including servo control and
image compression. As ColdFire-based systems proliferated, the desire for more precision on
input operands increased. The result was an improved ColdFire MAC with user-programmable
control to optionally enable use of fractional input operands.
EMAC improvements target three primary areas:
The three areas of functionality are addressed in detail in following sections. The logic required to
support this functionality is contained in a MAC module, as shown in
Freescale Semiconductor
• Signed and unsigned integer multiplies
• Multiply-accumulate operations supporting signed and unsigned integer operands as well
• Miscellaneous register operations
• Improved performance of 32 × 32 multiply operations.
• Addition of three more accumulators to minimize MAC pipeline stalls caused by exchanges
• A 48-bit accumulation data path to allow the use of a 40-bit product plus the addition of 8
as signed, fixed-point, fractional operands
between the accumulator and the pipeline’s general-purpose registers.
extension bits to increase the dynamic number range when implementing signal processing
algorithms.
Multiply-Accumulate Unit
MCF5235 Reference Manual, Rev. 2
Figure
4-1.
4-1