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
26-2 DS785UM1
Copyright 2007 Cirrus Logic
Keypad Interface
EP93xx User’s Guide
2
6
2
6
26
26.2 Theory of Operation
The circuitry scans an array of up to 64 keys. The keys are normally open, single pole
contacts arranged in an array of 8 rows by 8 columns. The array may be partially filled. The
key array rows are designated as ROW0 through ROW7, and the columns are designated as
COL0 through COL7.
Any 1 or 2 keys in the array that are pressed are de-bounced and decoded. If more than 2
keys are pressed, only the keys or apparent keys in the array with the lowest address will be
decoded.
Keys or apparent keys with address values greater than that of the lowest two will be ignored.
An apparent key is a condition that may occur when more than 2 keys are pressed. Apparent
keys are caused by alternate current paths in the key array.
A key address is the binary row number concatenated with the binary column address. Key
addresses range from 0x00 to 0x3F. A diagram of the key array is shown in Figure 26-2.
The circuitry scans the key array by driving each ROW line low, one line at a time. At the end
of each ROW time period, column data is read. The key array column lines are registered and
decoded by a multiplexer. The column address selects the column multiplexer input. Each of
the column lines is passively pulled up by the chip.
When a key is pressed, the column line for the key will be driven low when the row which
contains the key is driven low. On the next key array scan, the output of the multiplexer in the
chip will be asserted active when the row and column is the same as the key address. When
the multiplexer output is active then the key is detected and the address is stored, if it is one
of the first two from the start of a key array scan.
When more than 2 keys are pressed, it is possible to detect apparent keys. Apparent keys
look like actual pressed keys to the device but are not. An example of an apparent key is
described in “Apparent Key Detection”.