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
DS785UM1 20-3
Copyright 2007 Cirrus Logic
Real Time Clock With Software Trim
EP93xx User’s Guide
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20
20.1.1.4 Example - Measured Value Split Into Integer and Fractional
Component
The manufacturing tester measures the oscillator output to be 33,455.870 Hz. For the integer
portion, 33,455 - 32,768 is 687 cycles over the nominal frequency of the crystal. The integer
pre-load value for the counter should always be chosen so that the actual clock frequency is
faster than the value needed to generate a 1 Hz reference. Therefore, the
RTCSWComp.INT[15:0] value is loaded with the binary equivalent of 33,455-1 or 0x82AE.
The fractional component of the oscillator output was measured to be 0.870 Hz. Software
must adjust the clock so that the average number of cycles that are counted before
generating one 1 Hz clock is 33 455-1.
Because the clock frequency is 0.870 Hz faster than the integer value, the 1 Hz clock
generated by just the integer compensation is slightly faster than needed and may be slowed
down by deleting clocks.
The fractional compensation value must be programmed to delete 0.870 Hz on average to
bring the 1 Hz output frequency down to the proper value. Since the compensation procedure
is performed only every 32 seconds, the value must be set to delete (0.870*32) = 27.84
which, when rounded, is 28 clocks every 32 seconds. The rounded 0.16 cycles per
32 seconds (or 0.005 Hz) represents the error in compensation. The RTCSWComp.DEL[4:0]
fractional compensation value should be loaded with the hexadecimal equivalent of
28 - 1 or 0x1B.
20.1.1.5 Maximum Error Calculation vs. Real Time Clock Accuracy
The maximum error is 0.5½ clocks per 32 seconds. Therefore at 32.768 kHz, the maximum
error is:
(0.5½ clock / 32 sec) x (1 sec / 32,768 clocks nominal) x
(2592000 sec/1month) = 1.24 seconds/month maximum error
To maintain an accuracy of +/- 5 seconds per month the required interval is calculated to be:
(5 seconds/1 month) x (1 month/2,592,000 seconds) = 1.93E-6
= (1 second/32,768 clocks) x (½clock / X-interval seconds)
X-interval = 7.9 seconds
Therefore to maintain a 5-second-per-month accuracy the compensation circuit only has to
adjust within ½ of a 32.768 KHZ clock every 7.9 seconds. This could be done with a 3 bit
clock delete value and an 8 second (3 bits clocked by 1 Hz) counter. However, the
1.24 second per month number is better and has been implemented in this device.
20.1.1.6 Real-Time Interrupt
To allow a Real Time Interrupt to be generated, VIC2 INT[10] has been connected to the 1 Hz
clock. This interrupt should be configured as edge-triggered.