Owner's manual
Table Of Contents
- Contents
 - Preface
 - Introduction
- 1.1 Introduction
 - 1.2 EP93xx Features
 - 1.3 EP93xx Processor Applications
 - 1.4 EP93xx Processor Highlights
- 1.4.1 High-Performance ARM920T Core
 - 1.4.2 MaverickCrunch™ Co-processor for Ultra-Fast Math Processing
 - 1.4.3 MaverickKey™ Unique ID Secures Digital Content in OEM Designs
 - 1.4.4 Integrated Multi-Port USB 2.0 Full Speed Hosts with Transceivers
 - 1.4.5 Integrated Ethernet MAC Reduces BOM Costs
 - 1.4.6 8x8 Keypad Interface Reduces BOM Costs
 - 1.4.7 Multiple Booting Mechanisms Increase Flexibility
 - 1.4.8 Abundant General Purpose I/Os Build Flexible Systems
 - 1.4.9 General-Purpose Memory Interface (SDRAM, SRAM, ROM, FLASH)
 - 1.4.10 12-Bit Analog-to-Digital Converter (ADC) Provides an Integrated Touch-Screen Interface or General ADC Functionality
 - 1.4.11 Raster Analog / LCD Controller
 - 1.4.12 Graphics Accelerator
 - 1.4.13 PCMCIA Interface
 
 
 - ARM920T Core and Advanced High-Speed Bus (AHB)
 - MaverickCrunch Co-Processor
- 3.1 Introduction
 - 3.2 Programming Examples
 - 3.3 DSPSC Register
 - 3.4 ARM Co-Processor Instruction Format
 - 3.5 Instruction Set for the MaverickCrunch Co-Processor
- 3.5.1 Load and Store Instructions
 - 3.5.2 Move Instructions
 - 3.5.3 Accumulator and DSPSC Move Instructions
 - 3.5.4 Copy and Conversion Instructions
 - 3.5.5 Shift Instructions
 - 3.5.6 Compare Instructions
 - 3.5.7 Floating Point Arithmetic Instructions
 - 3.5.8 Integer Arithmetic Instructions
 - 3.5.9 Accumulator Arithmetic Instructions
 
 
 - Boot ROM
 - System Controller
 - Vectored Interrupt Controller
 - Raster Engine With Analog/LCD Integrated Timing and Interface
- 7.1 Introduction
 - 7.2 Features
 - 7.3 Raster Engine Features Overview
 - 7.4 Functional Details
- 7.4.1 VILOSATI (Video Image Line Output Scanner and Transfer Interface)
 - 7.4.2 Video FIFO
 - 7.4.3 Video Pixel MUX
 - 7.4.4 Blink Function
 - 7.4.5 Color Look-Up-Tables
 - 7.4.6 Color RGB Mux
 - 7.4.7 Pixel Shift Logic
 - 7.4.8 Grayscale/Color Generator for Monochrome/Passive Low Color Displays
 - 7.4.9 Hardware Cursor
 - 7.4.10 Video Timing
 - 7.4.11 Blink Logic
 - 7.4.12 Color Mode Definition
 
 - 7.5 Registers
 
 - Graphics Accelerator
 - 1/10/100 Mbps Ethernet LAN Controller
- 9.1 Introduction
 - 9.2 Descriptor Processor
- 9.2.1 Receive Descriptor Processor Queues
 - 9.2.2 Receive Descriptor Queue
 - 9.2.3 Receive Status Queue
- 9.2.3.1 Receive Status Format
 - 9.2.3.2 Receive Flow
 - 9.2.3.3 Receive Errors
 - 9.2.3.4 Receive Descriptor Data/Status Flow
 - 9.2.3.5 Receive Descriptor Example
 - 9.2.3.6 Receive Frame Pre-Processing
 - 9.2.3.7 Transmit Descriptor Processor Queues
 - 9.2.3.8 Transmit Descriptor Queue
 - 9.2.3.9 Transmit Descriptor Format
 - 9.2.3.10 Transmit Status Queue
 - 9.2.3.11 Transmit Status Format
 - 9.2.3.12 Transmit Flow
 - 9.2.3.13 Transmit Errors
 - 9.2.3.14 Transmit Descriptor Data/Status Flow
 
 - 9.2.4 Interrupts
 - 9.2.5 Initialization
 
 - 9.3 Registers
 
 - DMA Controller
- 10.1 Introduction
- 10.1.1 DMA Features List
 - 10.1.2 Managing Data Transfers Using a DMA Channel
 - 10.1.3 DMA Operations
 - 10.1.4 Internal M2P or P2M AHB Master Interface Functional Description
 - 10.1.5 M2M AHB Master Interface Functional Description
 - 10.1.6 AHB Slave Interface Limitations
 - 10.1.7 Interrupt Interface
 - 10.1.8 Internal M2P/P2M Data Unpacker/Packer Functional Description
 - 10.1.9 Internal M2P/P2M DMA Functional Description
 - 10.1.10 M2M DMA Functional Description
 - 10.1.11 DMA Data Transfer Size Determination
 - 10.1.12 Buffer Descriptors
 - 10.1.13 Bus Arbitration
 
 - 10.2 Registers
 
 - 10.1 Introduction
 - Universal Serial Bus Host Controller
 - Static Memory Controller
 - SDRAM, SyncROM, and SyncFLASH Controller
 - UART1 With HDLC and Modem Control Signals
 - UART2
 - UART3 With HDLC Encoder
 - IrDA
 - Timers
 - Watchdog Timer
 - Real Time Clock With Software Trim
 - I2S Controller
 - AC’97 Controller
 - Synchronous Serial Port
- 23.1 Introduction
 - 23.2 Features
 - 23.3 SSP Functionality
 - 23.4 SSP Pin Multiplex
 - 23.5 Configuring the SSP
- 23.5.1 Enabling SSP Operation
 - 23.5.2 Master/Slave Mode
 - 23.5.3 Serial Bit Rate Generation
 - 23.5.4 Frame Format
 - 23.5.5 Texas Instruments® Synchronous Serial Frame Format
 - 23.5.6 Motorola® SPI Frame Format
 - 23.5.7 Motorola SPI Format with SPO=0, SPH=0
 - 23.5.8 Motorola SPI Format with SPO=0, SPH=1
 - 23.5.9 Motorola SPI Format with SPO=1, SPH=0
 - 23.5.10 Motorola SPI Format with SPO=1, SPH=1
 - 23.5.11 National Semiconductor® Microwire™ Frame Format
 
 - 23.6 Registers
 
 - Pulse Width Modulator
 - Analog Touch Screen Interface
- 25.1 Introduction
 - 25.2 Touch Screen Controller Operation
- 25.2.1 Touch Screen Scanning: Four-wire and Eight-wire Operation
 - 25.2.2 Five-wire and Seven-wire Operation
 - 25.2.3 Direct Operation
 - 25.2.4 Measuring Analog Input with the Touch Screen Controls Disabled
 - 25.2.5 Measuring Touch Screen Resistance
 - 25.2.6 Polled and Interrupt-Driven Modes
 - 25.2.7 Touch Screen Package Dependency
 
 - 25.3 Registers
 
 - Keypad Interface
 - IDE Interface
 - GPIO Interface
 - Security
 - Glossary
 - EP93XX Register List
 

9-26 DS785UM1
Copyright 2007 Cirrus Logic
1/10/100 Mbps Ethernet LAN Controller
EP93xx User’s Guide
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 9.2.3.7 Transmit Descriptor Processor Queues
The transmit descriptor processor uses two circular queues in Host memory to manage the 
transfer of transmit data frame. The transmit descriptor queue is used to pass descriptors of 
user's data buffers from the Host to the MAC. The transmit status queue is used to pass 
information on the MAC's use of the data buffer back to the Host. Keeping these queues 
separate enables the use of burst transfers to and from the queues, reducing the overall 
amount of bus traffic and avoiding some potential latency problem.
 9.2.3.8 Transmit Descriptor Queue
The Transmit descriptors are passed from the Host to the MAC via the Transmit descriptor 
queue. The Transmit descriptor queue is a circular queue occupying a contiguous area of 
memory. The location and size of the queue are set at initialization by the Host writing to the 
Transmit Descriptor Queue Base Address Register and the Transmit Descriptor Queue Base 
Length. The base address must point to a word aligned memory location. The Transmit 
Descriptor Queue Base Length is set to the length in bytes of the queue. The length should 
be an integral number of descriptors and must not exceed 64 Kbytes total. The Transmit 
descriptor current address must also be set at initialization to point to the first descriptor to be 
used. This would normally be the first entry (same value as the base address).
Following initialization, the MAC will start to use descriptors from the Current Descriptor 
Address, wrapping back to the base pointer whenever the end of the queue is reached. In 
normal operation the Host should not need to access these registers after the initialization. 
The management of the descriptors is handled via the Transmit Descriptor Enqueue register.
Enqueueing descriptors is the process of adding descriptors to an existing queue. This is 
achieved in transmit by writing the number of additional descriptors to the Transmit Descriptor 
Enqueue register. The written value will be added to the previous value to keep a running 
total, as descriptors are read by the MAC, the total is adjusted. The running total is available 
by reading the enqueue register. One frame may be described by more than one descriptor, 
but the final descriptor will contain the EOF bit. Not all the descriptors for a frame need to be 
supplied at once.
No more than 255 descriptors may be added in one write. If a number greater than this needs 
to be written. the write should be broken up into more than one operation (that is, to add 300 
descriptors - first write 255, then write 45).










