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

14-16 DS785UM1
Copyright 2007 Cirrus Logic
UART1 With HDLC and Modem Control Signals
EP93xx User’s Guide
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14.5.2 Bus Bandwidth Requirements
There are two basic ways of moving data to and from the UART FIFOs:
• Direct DMA interface - This permits byte-wide access to the UART without using the
APB. The DMA block will pack or unpack individual bytes so that it reads or writes full
32-bit words rather than individual bytes.
• Accessing the UART via the APB - This requires APB/AHB bus bandwidth. Then, both a
read and write are required for each 8-bit data byte.
Bandwidth requirements also depend on the selected baud rate, character size, parity
selection, number of stop bits, and spacing between characters (if receiving).
For example, assume transmission protocols of 115,200 baud, 8-bit characters, even parity,
one stop bit, no space between characters. There are 11 bits per character, so
115,200 / 11 = 10,473 characters per second. If both transmitting and receiving, 20,945
characters per second pass through the UART. Accessing the UART through the DMA
interface requires one access per 32-bits, implying only 20,945 / 4 = 5,236 AHB accesses per
second. Accessing the UART through the APB requires two accesses per byte, implying
20,945 APB bus accesses.
As another example, assume 230,400 baud (the maximum with a UARTCLK equal to
7.3728 Mhz), 5-bit characters, no parity, one stop bit, and no space between characters.
There are 7 bits per character, so 230,400 / 7 = 32,914 characters per second. Simultaneous
transmitting and receiving implies 65,829 characters per second. Using the DMA interface
would result in 16,457 AHB accesses per second, while using the APB to access the UART
leads to 65,829 bus accesses per second.