National Semiconductor CP3UB17 Technical data

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CP3UB17 Reprogrammable Connectivity Processor with USB Interface

1.0 General Description

The CP3UB17 connectivity processor combines a powerful RISC core with on-chip SRAM and Flash memory for high computing bandwidth, hardware communications peripherals for high I/O bandwidth, and an external bus for system expandability.

On-chip communications peripherals include: USB controller, ACCESS.bus, Microwire/Plus, SPI, UART, and Advanced Audio Interface (AAI). Additional on-chip peripherals include DMA controller, PCM/CSVD conversion module, Timing and Watchdog Unit, Versatile Timer Unit, MultiFunction Timer, and Multi-Input Wakeup.

The CP3UB17 is backed up by the software resources designers need for rapid time-to-market, including an operating system, peripheral drivers, reference designs, and an integrated development environment.

CP3UB17 Connectivity Processor with USB Interface

PRELIMINARY

Sept. 2003

Block Diagram

12 MHz and 32 kHz

Oscillator

CR16C

CPU Core

Bus

Interface

Unit

Clock Generator

PLL and Clock

Generator

DMA

Controller

GPIOUSB

256K Bytes

Flash Program Memory

Peripheral

Controller

Audio

Interface

Power-on-Reset

Bus

Microwire/

SPI

8K Bytes

Flash

Data

CPU Core Bus

Interrupt

Control

Unit

Peripheral Bus

UART

CVSD/PCM

ACCESS

.bus

10K Bytes

Static

RAM

Versatile

Timer Unit

Powe r

Manage-

ment

Muti-Func-

tion Timer

Serial

Debug

Interface

Timing and

Watchdog

Unit

Multi-Input

Wake-Up

DS131

TRI-STATE is a registered trademark of National Semiconductor Corporation.

Table of Contents

1.0 General Description . . . . . . . . . . . . . . . . . . . . . . . . . . 1

CP3UB17

2.0 CPU Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

3.0 Device Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

3.1 CR16C CPU Core. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

3.2 Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

3.3 Input/Output Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

3.4 Bus Interface Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

3.5 Interrupt Control Unit (ICU) . . . . . . . . . . . . . . . . . . . . . . . 4

3.6 USB. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

3.7 Multi-Input Wake-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

3.8 Triple Clock and Reset . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.9 Power Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.10 Multi-Function Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.11 Versatile Timer Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.12 Timing and Watchdog Module . . . . . . . . . . . . . . . . . . . . 5

3.13 UART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.14 Microwire/SPI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.15 ACCESS.bus Interface . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.16 DMA CONTROLLER . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

3.17 Advanced Audio interface . . . . . . . . . . . . . . . . . . . . . . . . 6

3.18 CVSD/PCM Conversion Module. . . . . . . . . . . . . . . . . . . 6

3.19 Serial Debug Interface . . . . . . . . . . . . . . . . . . . . . . . . . . 6

3.20 Development Support . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

4.0 Device Pinouts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

4.1 Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

5.0 CPU Architecture. . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

5.1 General-Purpose Registers . . . . . . . . . . . . . . . . . . . . . 16

5.2 Dedicated Address Registers . . . . . . . . . . . . . . . . . . . . 16

5.3 Processor Status Register (PSR) . . . . . . . . . . . . . . . . . 17

5.4 Configuration Register (CFG) . . . . . . . . . . . . . . . . . . . . 18

5.5 Addressing Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

5.6 Stacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

5.7 Instruction Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

6.0 Memory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

6.1 Operating Environment . . . . . . . . . . . . . . . . . . . . . . . . . 25

6.2 Bus Interface Unit (BIU) . . . . . . . . . . . . . . . . . . . . . . . . 25

6.3 Bus Cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

6.4 BIU Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . 26

6.5 Wait and Hold States . . . . . . . . . . . . . . . . . . . . . . . . . . 28

7.0 System Configuration Registers . . . . . . . . . . . . . . . 29

7.1 Module Configuration Register (MCFG) . . . . . . . . . . . . 29

7.2 Module Status Register (MSTAT) . . . . . . . . . . . . . . . . . 29

8.0 Flash Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

8.1 Flash Memory Protection . . . . . . . . . . . . . . . . . . . . . . . 30

8.2 Flash Memory Organization . . . . . . . . . . . . . . . . . . . . . 30

8.3 Flash Memory Operations. . . . . . . . . . . . . . . . . . . . . . . 31

8.4 Information Block Words . . . . . . . . . . . . . . . . . . . . . . . . 32

8.5 Flash Memory Interface Registers . . . . . . . . . . . . . . . . 34

9.0 DMA Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

9.1 Channel Assignment. . . . . . . . . . . . . . . . . . . . . . . . . . . 40

9.2 Transfer Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

9.3 Operation Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

9.4 Software DMA Request . . . . . . . . . . . . . . . . . . . . . . . . 42

9.5 Debug Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

9.6 DMA Controller Register Set. . . . . . . . . . . . . . . . . . . . . 42

10.0 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

10.1 Non-Maskable Interrupts. . . . . . . . . . . . . . . . . . . . . . . . 46

10.2 Maskable Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

10.3 Interrupt Controller Registers . . . . . . . . . . . . . . . . . . . . 46

10.4 Maskable Interrupt Sources . . . . . . . . . . . . . . . . . . . . . 48

10.5 Nested Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

11.0 Triple Clock and Reset . . . . . . . . . . . . . . . . . . . . . . . 50

11.1 External Crystal Network . . . . . . . . . . . . . . . . . . . . . . . 51

11.2 Main Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

11.3 Slow Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

11.4 PLL Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

11.5 System Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

11.6 Auxiliary Clocks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

11.7 Power-On Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

11.8 External Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

11.9 Clock and Reset Registers . . . . . . . . . . . . . . . . . . . . . . 53

12.0 Power Management. . . . . . . . . . . . . . . . . . . . . . . . . . 55

12.1 Active Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

12.2 Power Save Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

12.3 Idle Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

12.4 Halt Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

12.5 Clock Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

12.6 Power Management Registers . . . . . . . . . . . . . . . . . . . 56

12.7 Switching Between Power Modes. . . . . . . . . . . . . . . . . 57

13.0 Multi-Input Wake-Up . . . . . . . . . . . . . . . . . . . . . . . . . 59

13.1 Multi-Input Wake-Up Registers . . . . . . . . . . . . . . . . . . . 59

13.2 Programming Procedures . . . . . . . . . . . . . . . . . . . . . . . 61

14.0 Input/Output Ports. . . . . . . . . . . . . . . . . . . . . . . . . . . 62

14.1 Port Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

14.2 Open-Drain Operation. . . . . . . . . . . . . . . . . . . . . . . . . . 65

15.0 USB Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

15.1 Functional States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

15.2 Endpoint Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

15.3 USB Controller Registers . . . . . . . . . . . . . . . . . . . . . . . . 70

15.4 Transceiver Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

16.0 Advanced Audio Interface. . . . . . . . . . . . . . . . . . . . . 86

16.1 Audio Interface Signals . . . . . . . . . . . . . . . . . . . . . . . . . 86

16.2 Audio Interface Modes . . . . . . . . . . . . . . . . . . . . . . . . . . 86

16.3 Bit Clock Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

16.4 Frame Clock Generation . . . . . . . . . . . . . . . . . . . . . . . . 89

16.5 Audio Interface Operation . . . . . . . . . . . . . . . . . . . . . . . 89

16.6 Communication Options. . . . . . . . . . . . . . . . . . . . . . . . . 91

16.7 Audio Interface Registers. . . . . . . . . . . . . . . . . . . . . . . . 94

17.0 CVSD/PCM Conversion Module . . . . . . . . . . . . . . . 101

17.1 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

17.2 PCM Conversions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

17.3 CVSD Conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

17.4 PCM to CVSD Conversion . . . . . . . . . . . . . . . . . . . . . . 102

17.5 CVSD to PCM Conversion . . . . . . . . . . . . . . . . . . . . . . 102

17.6 Interrupt Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

17.7 DMA Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

17.8 Freeze . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

17.9 CVSD/PCM Converter Registers. . . . . . . . . . . . . . . . . 103

18.0 UART Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

18.1 Functional Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 106

18.2 UART Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

18.3 UART Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

18.4 Baud Rate Calculations . . . . . . . . . . . . . . . . . . . . . . . . 114

19.0 Microwire/SPI Interface . . . . . . . . . . . . . . . . . . . . . . 116

19.1 Microwire Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . 116

19.2 Master Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

19.3 Slave Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

19.4 Interrupt Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

19.5 Microwire Interface Registers . . . . . . . . . . . . . . . . . . . 119

20.0 ACCESS.bus Interface. . . . . . . . . . . . . . . . . . . . . . . 122

20.1 ACB Protocol Overview . . . . . . . . . . . . . . . . . . . . . . . . 122

20.2 ACB Functional Description . . . . . . . . . . . . . . . . . . . . . 124

20.3 ACCESS.bus Interface Registers . . . . . . . . . . . . . . . . 126

20.4 Usage Hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

21.0 Timing and Watchdog Module . . . . . . . . . . . . . . . . 131

21.1 TWM Structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

21.2 Timer T0 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

21.3 Watchdog Operation . . . . . . . . . . . . . . . . . . . . . . . . . . 132

21.4 TWM Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

21.5 Watchdog Programming Procedure. . . . . . . . . . . . . . . 134

22.0 Multi-Function Timer . . . . . . . . . . . . . . . . . . . . . . . . 135

22.1 Timer Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

22.2 Timer Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . 136

22.3 Timer Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140

22.4 Timer I/O Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . 140

22.5 Timer Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

23.0 Versatile Timer Unit (VTU). . . . . . . . . . . . . . . . . . . . 144

23.1 VTU Functional Description . . . . . . . . . . . . . . . . . . . . . 144

23.2 VTU Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

24.0 Register Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152

25.0 Register Bit Fields . . . . . . . . . . . . . . . . . . . . . . . . . . 162

26.0 Electrical Characteristics . . . . . . . . . . . . . . . . . . . . 172

26.1 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . 172

26.2 DC Electrical Characteristics . . . . . . . . . . . . . . . . . . . . 172

26.3 USB Transceiver Electrical Characteristics . . . . . . . . . 173

26.4 Flash Memory On-Chip Programming. . . . . . . . . . . . . 174

26.5 Output Signal Levels . . . . . . . . . . . . . . . . . . . . . . . . . . 175

26.6 Clock and Reset Timing. . . . . . . . . . . . . . . . . . . . . . . . 175

26.7 UART Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177

26.8 I/O Port Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178

26.9 Advanced Audio Interface (AAI) Timing. . . . . . . . . . . . 179

26.10 Microwire/SPI Timing . . . . . . . . . . . . . . . . . . . . . . . . . . 181

26.11 ACCESS.bus Timing . . . . . . . . . . . . . . . . . . . . . . . . . . 186

26.12 USB Port AC Characteristics . . . . . . . . . . . . . . . . . . . . 189

26.13 Multi-Function Timer (MFT) Timing . . . . . . . . . . . . . . . 189

26.14 Versatile Timing Unit (VTU) Timing . . . . . . . . . . . . . . . 190

26.15 External Bus Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . 191

27.0 Revision History. . . . . . . . . . . . . . . . . . . . . . . . . . . . 196

28.0 Device Pinouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197

29.0 Physical Dimensions . . . . . . . . . . . . . . . . . . . . . . . . 199

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2.0 CPU Features

CPU Features

 Fully static RISC processor core, capable of operating

from 0 to 24 MHz with zero wait/hold states

 Minimum 41.7 ns instruction cycle time with a 24-MHz in-

ternal clock frequency, based on a 12-MHz external input

 30 independently vectored peripheral interrupts

On-Chip Memory

 256K bytes reprogrammable Flash program memory  8K bytes Flash data memory  10K bytes of static RAM data memory  Addresses up to 8 Mbytes of external memory

Broad Range of Hardware Communications Peripherals

 Full-speed USB node including seven Endpoint-FIFOs

conforming to USB 1.1 specification

 ACCESS.bus serial bus (compatible with Philips I  8/16-bit SPI, Microwire/Plus serial interface  Universal Asynchronous Receiver/Transmitter (UART)  Advanced Audio Interface (AAI) to connect to external 8/

13-bit PCM Codecs as well as to ISDN-Controllers through the IOM-2 interface (slave only)

 PCM/CVSD converter supporting one bidirectional audio

connection

General-Purpose Hardware Peripherals

 Dual 16-bit Multi-Function Timer  Versatile Timer Unit with four subsystems (VTU)  Four channel DMA controller  Timing and Watchdog Unit

C bus)

CP3UB17

Flexible I/O

 Up to 37 general-purpose I/O pins (shared with on-chip

peripheral I/O pins)

 Programmable I/O pin characteristics: TRI-STATE out-

put, push-pull output, weak pull-up input, high-impedance input

 Schmitt triggers on general purpose inputs  Multi-Input Wakeup

Extensive Power and Clock Management Support

 On-chip Phase Locked Loop  Support for multiple clock options  Dual clock and reset  Power-down modes

Power Supply

 I/O port operation at 2.5V to 3.3V  Core logic operation at 2.5V  On-chip power-on reset

Temperature Range

 -40°C to +85°C (Industrial)

Packages

 CSP-48, LQFP-100

Complete Development Environment

 Pre-integrated hardware and software support for rapid

prototyping and production

 Integrated environment  Project manager  Multi-file C source editor

CP3UB17 Connectivity Processor Selection Guide

NSID

CP3UB17G38 24 -40° to +85°C 256 8 10 22 37 LQFP-100

CP3UB17K38 24 -40° to +85°C 256 8 10 0 21 CSP-48

Speed

(MHz)

Temp. Range

Program

Flash

(kBytes)

Data

Flash

(kBytes)

SRAM

(kBytes)

External Address

Lines

I/Os

Package

3 www.national.com

Typ e

3.0 Device Overview

The CP3UB17 connectivity processor is a complete microcomputers with all system timing, interrupt logic, program

CP3UB17

memory, data memory, I/O ports included on-chip, making them well-suited to a wide range of embedded applications. The block diagram on page 1 shows the major on-chip components of the CP3UB17.

3.1 CR16C CPU CORE

The CP3UB17 implements the CR16C CPU core module. The high performance of the CPU core results from the implementation of a pipelined architecture with a two-bytesper-cycle pipelined system bus. As a result, the CPU can support a peak execution rate of one instruction per clock cycle.

For more information, please refer to the CR16C Programmer’s Reference Manual (document number 424521772101, which may be downloaded from National’s web site at http://www.national.com).

The I/O pin characteristics are fully programmable. Each pin can be configured to operate as a TRI-STATE output, pushpull output, weak pull-up input, or high-impedance input.

3.4 BUS INTERFACE UNIT

The Bus Interface Unit (BIU) controls access to internal/external memory and I/O. It determines the configured parameters for bus access (such as the number of wait states for memory access) and issues the appropriate bus signals for each requested access.

The BIU uses a set of control registers to determine how many wait states and hold states are used when accessing Flash program memory, and the I/O area (Port B and Port C). At start-up, the configuration registers are set for slowest possible memory access. To achieve fastest possible program execution, appropriate values must be programmed. These settings vary with the clock frequency and the type of off-chip device being accessed.

3.2 MEMORY

The CP3UB17 supports a uniform linear address space of up to 16 megabytes. Three types of on-chip memory occupy specific regions within this address space:

 256K bytes of Flash program memory  8K bytes of Flash data memory  10K bytes of static RAM  Up to 8M bytes of external memory (100-pin devices )

The 256K bytes of Flash program memory are used to store the application program and real-time operating system. The Flash memory has security features to prevent unintentional programming and to prevent unauthorized access to the program code. This memory can be programmed with an external programming unit or with the device installed in the application system (in-system programming).

The 8K bytes of Flash data memory are used for non-volatile storage of data entered by the end-user, such as configuration settings.

The 10K bytes of static RAM are used for temporary storage of data and for the program stack and interrupt stack. Read and write operations can be byte-wide or word-wide, depending on the instruction executed by the CPU.

Up to 8M bytes of external memory can be added on an external bus. The external bus is only available on devices in 100-pin packages.

For Flash program and data memory, the device internally generates the necessary voltages for programming. No additional power supply is required.

3.3 INPUT/OUTPUT PORTS

The device has up to 37 software-configurable I/O pins, organized into five ports called Port B, Port C, Port G, Port H, and Port I. Each pin can be configured to operate as a general-purpose input or general-purpose output. In addition, many I/O pins can be configured to operate as inputs or outputs for on-chip peripheral modules such as the UART, timers, or Microwire/SPI interface.

3.5 INTERRUPT CONTROL UNIT (ICU)

The ICU receives interrupt requests from internal and external sources and generates interrupts to the CPU. An interrupt is an event that temporarily stops the normal flow of program execution and causes a separate interrupt handler to be executed. After the interrupt is serviced, CPU execution continues with the next instruction in the program following the point of interruption.

Interrupts from the timers, UART, Microwire/SPI interface, and Multi-Input Wake-Up, are all maskable interrupts; they can be enabled or disabled by software. There are 32 of these maskable interrupts, assigned to 32 linear priority levels.

The highest-priority interrupt is the Non-Maskable Interrupt

), which is generated by a signal received on the NMI

(NMI input pin.

3.6 USB

The USB node is a Universal Serial Bus (USB) Node controller compatible with USB Specification, 1.0 and 1.1. It integrates the required USB transceiver, the Serial Interface Engine (SIE), and USB endpoint FIFOs. A total of seven endpoint pipes are supported: one bidirectional pipe for the mandatory control EP0 and an additional six pipes for unidirectional endpoints to support USB interrupt, bulk, and isochronous data transfers.

3.7 MULTI-INPUT WAKE-UP

The Multi-Input Wake-Up (MIWU) module can be used for either of two purposes: to provide inputs for waking up (exiting) from the Halt, Idle, or Power Save mode; or to provide general-purpose edge-triggered maskable interrupts from external sources. This 16-channel module generates four programmable interrupts to the CPU based on the signals received on its 16 input channels. Channels can be individually enabled or disabled, and programmed to respond to positive or negative edges.

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3.8 TRIPLE CLOCK AND RESET

The Triple Clock and Reset module generates a high-speed main System Clock from an external crystal network. It also provides the main system reset signal and a power-on reset function.

This module generates a slow System Clock (32.768 kHz) from an optional external crystal network. The Slow Clock is used for operating the device in power-save mode. The

32.768 kHz external crystal network is optional, because the low speed System Clock can be derived from the highspeed clock by a prescaler.

Also, two independent clocks divided down from the high speed clock are available on output pins.

The Triple Clock and Reset module provides the clock signals required for the operation of the various CP3UB17 onchip modules. From external crystal networks, it generates the Main Clock, which can be scaled up to 24 MHz from an external 12 MHz input clock, and a 32.768 kHz secondary System Clock. The 12 MHz external clock is primarily used as the reference frequency for the on-chip PLL. Also the clock for modules which require a fixed clock rate (e.g. the PCM/CVSD transcoder) is generated through prescalers from the 12 MHz clock. The PLL generates the input clock for the USB node and may be used to drive the high-speed System Clock through a prescaler. Alternatively, the high speed System Clock can be derived directly from the 12 MHz Main Clock.

In addition, this module generates the device reset by using reset input signals coming from an external reset and various on-chip modules.

3.9 POWER MANAGEMENT

The Power Management Module (PMM) improves the efficiency of the device by changing the operating mode and power consumption to match the required level of activity.

The device can operate in any of four power modes:

 Active—The device operates at full speed using the high-

frequency clock. All device functions are fully operational.

 Power Save —The device operates at reduced speed us-

ing the Slow Clock. The CPU and some modules can continue to operate at this low speed.

 Idle—The device is inactive except for the Power Man-

agement Module and Timing and Watchdog Module, which continue to operate using the Slow Clock.

 Halt—The device is inactive but still retains its internal

state (RAM and register contents).

3.10 MULTI-FUNCTION TIMER

The Multi-Function Timer (MFT) module contains a pair of 16-bit timer/counter registers. Each timer/counter unit can be configured to operate in any of the following modes:

 Processor-Independent Pulse Width Modulation (PWM)

mode—Generates pulses of a specified width and duty

cycle and provides a general-purpose timer/counter.

 Dual Input Capture mode—Measures the elapsed time

between occurrences of external event and provides a general-purpose timer/counter.

 Dual Independent Timer mode—Generates system tim-

ing signals or counts occurrences of external events.

 Single Input Capture and Single Timer mode—Provides

one external event counter and one system timer.

3.11 VERSATILE TIMER UNIT

The Versatile Timer Unit (VTU) module contains four independent timer subsystems, each operating in either dual 8bit PWM configuration, as a single 16-bit PWM timer, or a 16-bit counter with two input capture channels. Each of the four timer subsystems offer an 8-bit clock prescaler to accommodate a wide range of frequencies.

3.12 TIMING AND WATCHDOG MODULE

The Timing and Watchdog Module (TWM) contains a RealTime timer and a Watchdog unit. The Real-Time Clock Timing function can be used to generate periodic real-time based system interrupts. The timer output is one of 16 inputs to the Multi-Input-Wake-Up module which can be used to exit from a power-saving mode. The Watchdog unit is designed to detect the application program getting stuck in an infinite loop resulting in loss of program control or “runaway” programs. When the watchdog triggers, it resets the device. The TWM is clocked by the low-speed System Clock.

3.13 UART

The UART supports a wide range of programmable baud rates and data formats, parity generation, and several error detection schemes. The baud rate is generated on-chip, under software control.

The UART offers a wake-up condition from the power-save mode using the Multi-Input Wake-Up module.

3.14 MICROWIRE/SPI

The Microwire/SPI (MWSPI) interface module supports synchronous serial communications with other devices that conform to Microwire or Serial Peripheral Interface (SPI) specifications. It supports 8-bit and 16-bit data transfers.

The Microwire interface allows several devices to communicate over a single system consisting of four wires: serial in, serial out, shift clock, and slave enable. At any given time, the Microwire interface operates as the master or a slave. The Microwire interface supports the full set of slave select for multi-slave implementation.

In master mode, the shift clock is generated on chip under software control. In slave mode, a wake-up out of powersave mode is triggered using the Multi-Input Wake-Up module.

3.15 ACCESS.BUS INTERFACE

The ACCESS.bus interface module (ACB) is a two-wire serial interface with the ACCESS.bus physical layer. It is also compatible with Intel’s System Management Bus (SMBus) and Philips’ I a bus master or slave, and can maintain bidirectional communications with both multiple master and slave devices.

The ACCESS.bus receiver can trigger a wake-up condition out of the low-power modes using the Multi-Input Wake-Up module.

C bus. The ACB module can be configured as

CP3UB17

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3.16 DMA CONTROLLER

The Direct Memory Access Controller (DMAC) can speed up data transfer between memory and I/O devices or be-

CP3UB17

tween two memories, relative to data transfers performed directly by the CPU. A method called cycle-stealing allows the CPU and the DMAC to use the core bus in parallel. The DMAC implements four independent DMA channels. DMA requests from a primary and a secondary source are recognized for each DMA channel, as well as a software DMA request issued directly by the CPU. Table 1 shows the DMA channel assignment on the CP3UB17 architecture. The following on-chip modules can assert a DMA request to the DMAC:

 CR16C (Software DMA request)  USB  UART  Advanced Audio Interface  PCM/CVSD Converter

Table 1 shows how the four DMA channels are assigned to the modules listed above.

Table 1 DMA Channel Assignment

Channel

Primary/

Secondary

Primary USB Read/Write

Secondary UART Read

Primary UART Write

Secondary Unused N/A

Peripheral Transaction

3.18 CVSD/PCM CONVERSION MODULE

The CVSD/PCM module performs conversion between CVSD data and PCM data, in which the PCM data can be 8-bit µ-Law, 8-bit A-Law, or 13-bit to 16-bit Linear.

3.19 SERIAL DEBUG INTERFACE

The Serial Debug Interface module (SDI module)provides a JTAG-based serial link to an external debugger, for example running on a PC. In addition, the SDI module integrates an on-chip debug module, which allows the user to set up to four hardware breakpoints on instruction execution and data transfer. The SDI module can act as a CPU bus master to access all memory mapped resources, such as RAM and peripherals. Therefore it also allows for fast program code download into the on-chip Flash program memory using the JTAG interface.

3.20 DEVELOPMENT SUPPORT

National Semiconductor offers a complete and industryproven application development environment for CP3UB17 applications, including the IAR Embedded Workbench, iSYSTEM winIDEA and iC3000 Active Emulator, Development Board, and Application Software. See your National Semiconductor sales representative for current information on availability and features of emulation equipment and evaluation boards.

Primary AAI Read

Secondary CVSD/PCM Read

Primary AAI Write

Secondary CVSD/PCM Write

3.17 ADVANCED AUDIO INTERFACE

The audio interface provides a serial synchronous, full-duplex interface to CODECs and similar serial devices. Transmit and receive paths operate asynchronously with respect to each other. Each path uses three signals for communication: shift clock, frame synchronization, and data.

In case receive and transmit use separate shift clocks and frame sync signals, the interface operates in its asynchronous mode. Alternatively, the transmit and receive path can share the same shift clock and frame sync signals for synchronous mode operation.

The interface can handle data words of either 8- or 16-bit length and data frames can consist of up to four slots.

In the normal mode of operation, the interface only transfers one word at a periodic rate. In the network mode, the interface transfers multiple words at a periodic rate. The periodic rate is also called a data frame and each word within one frame is called a slot. The beginning of each new data frame is marked by the frame sync signal.

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4.0 Device Pinouts

CP3UB17

2 MHz Crystal

or Ext. Clock

32.768 kHz Crystal

Powe r

Supply

Chip Reset

JTAG I/F to

Debugger/

Programmer

ACCESS.bus

USB

Mode

Selection

X1CKI X1CKO

X2CKI X2CKO

AVCC AGND VCC

IOVCC GND

RESET

TMS TDI TDO

TCK RDY

SDA SCL

D D- UVCC UGND

ENV0 ENV1 ENV2

CP3UB17

(LQFP-100)

PB[7:0] PC[7:0] A[21:0]

SEL0 SEL1 SEL2

SELIO

WR0 WR1

PI0 PI1 PI3 PI4 PI5

PI6/WUI9

PI7/TA

PG0/RXD/WUI10 PG1/TXD/WUI11

PG2/RTS/WUI12

PG3/CTS/WUI13

PH0/MSK/TIO1 PH1/MDIDO/TIO2 PH2/MDODI/TIO3

PH3/MWCS/TIO4

PH4/SCK/TIO5

PH5/SFS/TIO6 PH6/STD/TIO7

PH7/SRD/TIO8

PG5/SRFS/NMI

PI2/SRCLK

12 MHz Crystal

or Ext. Clock

External Bus

32.768 kHz

Interface

GPIO

MIWU

JTAG I/F to

MFT

Programmer

UART/ MIWU

MICROWIRE/ SPI/ VTU

AAI/ VTU

AAI/NMI

AAI

Crystal/

Powe r

Supply

Chip Reset

Debugger/

Mode

Selection

X1CKI X1CKO

X2CKI X2CKO

AVCC AGND

VCC

IOVCC GND

RESET

TMS TDI TDO

TCK RDY

ENV0 ENV1

CP3UB17

(CSP-48)

PG0/RXD/WUI10 PG1/TXD/WUI11

PG2/RTS/WUI12

PG3/CTS/WUI13

PH0/MSK/TIO1 PH1/MDIDO/TIO2 PH2/MDODI/TIO3

PH3/MWCS/TIO4

PH4/SCK/TIO5 PH5/SFS/TIO6 PH6/STD/TIO7 PH7/SRD/TIO8

PG5/SRFS/NMI

UVCC UGND

PI0 PI1

PI3 PI4 PI5

PI6/WUI9

PI7/TA

PI2/SRCLK

D-

USB

GPIO

MIWU

MFT

UART/ MIWU

MICROWIRE SPI/ VTU

AAI/ VTU

AAI/NMI

AAI

DS139

Table 2 Pin Assignments for 100-Pin Package

Pin Name Alternate Function(s) Pin Number Type

A14 1 O

A13 2 O

A12 3 O

A11 4 O

A10 5 O

PH6 STD/TIO7 6 GPIO

PH7 SRD/TIO8 7 GPIO

ENV1 8 I/O

A9 9 O

A8 10 O

A7 11 O

A6 12 O

A5 13 O

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Table 2 Pin Assignments for 100-Pin Package

Pin Name Alternate Function(s) Pin Number Type

CP3UB17

A4 14 O

VCC 15 PWR

X2CKI 16 I

X2CKO 17 O

GND 18 PWR

AVC C 19 PWR

AGND 20 PWR

IOVCC 21 PWR

X1CKO 22 O

X1CKI 23 I

GND 24 PWR

A3 26 O

A2 27 O

A1 28 O

A0 29 O

PI0 30 GPIO

PI1 31 GPIO

PI2 SRCLK 32 GPIO

PB0 D0 33 GPIO

PB1 D1 34 GPIO

PB2 D2 35 GPIO

PB3 D3 36 GPIO

PB4 D4 37 GPIO

PB5 D5 38 GPIO

PB6 D6 39 GPIO

PB7 D7 40 GPIO

GND 41 PWR

IOVCC 42 PWR

PI3 43 GPIO

PI4 44 GPIO

PI5 45 GPIO

PI6 WUI9 46 GPIO

PI7 TA 47 GPIO

PG0 RXD/WUI10 48 GPIO

PG1 TXD/WUI11 49 GPIO

PC0 D8 50 GPIO

PG2 RTS

PG3 CTS

PC1 D9 53 GPIO

PC2 D10 54 GPIO

PC3 D11 55 GPIO

PC4 D12 56 GPIO

PC5 D13 57 GPIO

/WUI12 51 GPIO

/WUI13 52 GPIO

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Table 2 Pin Assignments for 100-Pin Package

Pin Name Alternate Function(s) Pin Number Type

PC6 D14 58 GPIO

PC7 D15 59 GPIO

PG5 SRFS/NMI

TMS 61 I

TCK 62 I

TDI 63 I

GND 64 PWR

IOVCC 65 PWR

ENV2 66 I/O

SEL0 67 O

SCL 68 I/O

SDA 69 I/O

TDO 70 O

D- 71 I/O

D+ 72 I/O

UVCC 73 PWR

UGND 74 PWR

RDY 75 O

SEL1 76 O

SEL2 77 O

SELIO 78 O

A21 79 O

A20 80 O

PH0 MSK/TIO1 81 GPIO

PH1 MDIDO/TIO2 82 GPIO

PH2 MDODI/TIO3 83 GPIO

PH3 MWCS

ENV0 85 I/O

IOVCC 86 PWR

GND 87 PWR

VCC 88 PWR

GND 89 PWR

RESET 90 I

RD 91 O

WR0 92 O

WR1 93 O

A19 94 O

A18 95 O

A17 96 O

A16 97 O

A15 98 O

/TIO4 84 GPIO

60 GPIO

CP3UB17

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Table 2 Pin Assignments for 100-Pin Package

Pin Name Alternate Function(s) Pin Number Type

CP3UB17

PH4 SCK/TIO5 99 GPIO

PH5 SFS/TIO6 100 GPIO

Note 1: The ENV0, ENV1, ENV2, TCK, TDI, and TMS pins each have a weak pull-up to keep the input from floating. Note 2: The RESET Note 3: These functions are always enabled, due to the direct low-impedance path to these pins.

input has a weak pulldown.

Table 3 Pin Assignments for 48-Pin Package

Pin Name Alternate Function(s) Pin Number Type

PH6 STD/TIO7

PH7 SRD/TIO8

ENV1

VCC

X2CKI

X2CKO

GND

AVC C

AGND

IOVCC

X1CKO

X1CKI

GND

PI0

PI1

PI2 SRCLK

PI3

PI4

PI5

PI6 WUI9

PI7 TA

PG0 RXD/WUI10

PG1 TXD/WUI11

PG2 RTS

PG3 CTS

/WUI12

/WUI13

PG5 SRFS/NMI

TMS

TCK

TDI

GND

IOVCC

TDO

D-

D+

UVCC

UGND

GPIO

I/O

PWR

GPIO

PWR

O, GPIO

I/O

PWR, I/O

PWR, O

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Pin Name Alternate Function(s) Pin Number Type

RDY

PH0 MSK/TIO1

PH1 MDIDO/TIO2

PH2 MDODI/TIO3

PH3 MWCS

/TIO4

ENV0

VCC

GND

RESET

PH4 SCK/TIO5

PH5 SFS/TIO6

Note 1: The ENV0 and ENV1, TCK, TDI and TMS pins each have a weak pull-up to keep the input from floating. Note 2: The RESET Note 3: These functions are always enabled, due to the direct low-impedance path to these pins.

input has a weak pulldown.

CP3UB17

GPIO

I/O

PWR

GPIO

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4.1 PIN DESCRIPTION

Some pins may be enabled as general-purpose I/O-port pins or as alternate functions associated with specific peripherals or interfaces. These pins may be individually con-

CP3UB17

Table 4 CP3UB17 Pin Description for the 100-Pin LQFP Package

figured as port pins, even when the associated peripheral or interface is enabled. Table 4 lists the device pins.

Name Pins I/O Primary Function

X1CKI 1 Input 12 MHz Oscillator Input None None

X1CKO 1 Output 12 MHz Oscillator Output None None

X2CKI 1 Input 32 kHz Oscillator Input None None

X2CKO 1 Output 32 kHz Oscillator Output None None

AVCC 1 Input PLL Analog Power Supply None None

IOVCC 4 Input 2.5V - 3.3V I/O Power Supply None None

VCC 2 Input

GND 6 Input Reference Ground None None

AGND 1 Input PLL Analog Ground None None

RESET

TMS 1 Input

TDI 1 Input

TDO 1 Output JTAG Test Data Output None None

TCK 1 Input

RDY

1 Input Chip general reset None None

1 Output NEXUS Ready Output None None

2.5V Core Logic Power Supply

JTAG Test Mode Select (with internal weak pull-up)

JTAG Test Data Input (with internal weak pull-up)

JTAG Test Clock Input (with internal weak pull-up)

Alternate

Name

None None

Alternate Function

PG0 1 I/O Generic I/O

PG1 1 I/O Generic I/O

PG2 1 I/O Generic I/O

PG3 1 I/O Generic I/O

PG5 1 I/O Generic I/O

PH0 1 I/O Generic I/O

PH1 1 I/O Generic I/O

PH2 1 I/O Generic I/O

RXD UART Receive Data Input

WUI10 Multi-Input Wake-Up Channel 10

TXD UART Transmit Data Output

WUI11 Multi-Input Wake-Up Channel 11

RTS

WUI12 Multi-Input Wake-Up Channel 12

CTS UART Clear-To-Send Input

WUI13 Multi-Input Wake-Up Channel 13

SRFS AAI Receive Frame Sync

NMI

MSK SPI Shift Clock

TIO1 Versatile Timer Channel 1

MDIDO SPI Master In Slave Out

TIO2 Versatile Timer Channel 2

MDODI SPI Master Out Slave In

TIO3 Versatile Timer Channel 3

UART Ready-To-Send Output

Non-Maskable Interrupt Input

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CP3UB17

Name Pins I/O Primary Function

PH3 1 I/O Generic I/O

PH4 1 I/O Generic I/O

PH5 1 I/O Generic I/O

PH6 1 I/O Generic I/O

PH7 1 I/O Generic I/O

PI0 1 I/O Generic I/O None None

PI1 1 I/O Generic I/O None None

PI2 1 I/O Generic I/O SRCLK AAI Receive Clock

PI3 1 I/O Generic I/O None None

PI4 1 I/O Generic I/O None None

PI5 1 I/O Generic I/O None None

Alternate

Name

MWCS

TIO4 Versatile Timer Channel 4

SCK AAI Clock

TIO5 Versatile Timer Channel 5

SFS AAI Frame Synchronization

TIO6 Versatile Timer Channel 6

STD AAI Transmit Data Output

TIO7 Versatile Timer Channel 7

SRD AAI Receive Data Input

TIO8 Versatile Timer Channel 8

SPI Slave Select Input

Alternate Function

PI6 1 I/O Generic I/O WUI9 Multi-Input Wake-Up Channel 9

PI7 1 I/O Generic I/O TA Multi Function Timer Port A

SDA 1 I/O ACCESS.bus Serial Data None None

SCL 1 I/O ACCESS.bus Clock None None

D+ 1 I/O USB D+ Upstream Port None None

D- 1 I/O USB D- Upstream Port None None

UVCC 1 Input 3.3V USB Transceiver Supply None None

UGND 1 Input USB Transceiver Ground None None

PB[7:0] 8 I/O Generic I/O D[7:0] External Data Bus Bit 0 to 7

PC[7:0] 8 I/O Generic I/O D[15:8] External Data Bus Bit 8 to 15

A[21:0] 22 Output

SEL0

SEL1

SEL2

SELIO

WR0

WR1

ENV0 1 I/O

1 Output Chip Select for Zone 0 None None

1 Output Chip Select for Zone 1 None None

1 Output Chip Select for Zone 2 None None

1 Output Chip Select for Zone I/O Zone None None

1 Output External Memory Write Low Byte None None

1 Output External Memory Write High Byte None None

1 Output External Memory Read None None

External Address Bus Bit 0 to 21

Special mode select input with internal pull-up during reset

None None

PLLCLK PLL Clock Output

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Name Pins I/O Primary Function

Alternate

Name

Alternate Function

CP3UB17

ENV1 1 I/O

ENV2 1 I/O

Name Pins I/O Primary Function

X1CKI 1 Input 12 MHz Oscillator Input None None

X1CKO 1 Output 12 MHz Oscillator Output None None

X2CKI 1 Input 32 kHz Oscillator Input None None

X2CKO 1 Output 32 kHz Oscillator Output None None

AVCC 1 Input PLL Analog Power Supply None None

IOVCC 2 Input 2.5V - 3.3V I/O Power Supply None None

VCC 2 Input

GND 4 Input Reference Ground None None

AGND 1 Input PLL Analog Ground None None

RESET

TMS 1 Input

TDI 1 Input

1 Input Chip general reset None None

Special mode select input with internal pull-up during reset

Table 5 CP3UB17 Pin Description for the 48-Pin CSP

2.5V Core Logic Power Supply

JTAG Test Mode Select (with internal weak pull-up)

JTAG Test Data Input (with internal weak pull-up)

CPUCLK CPU Clock Output

SLOWCLK Slow Clock Output

Alternate

Name

None None

Alternate Function

TDO 1 Output JTAG Test Data Output None None

TCK 1 Input

RDY

PG0 1 I/O Generic I/O

PG1 1 I/O Generic I/O

PG2 1 I/O Generic I/O

PG3 1 I/O Generic I/O

PG5 1 I/O Generic I/O

PH0 1 I/O Generic I/O

PH1 1 I/O Generic I/O

1 Output NEXUS Ready Output None None

JTAG Test Clock Input (with internal weak pull-up)

None None

RXD UART Receive Data Input

WUI10 Multi-Input Wake-Up Channel 10

TXD UART Transmit Data Output

WUI11 Multi-Input Wake-Up Channel 11

RTS

WUI12 Multi-Input Wake-Up Channel 12

CTS

WUI13 Multi-Input Wake-Up Channel 13

SRFS AAI Receive Frame Sync

NMI

MSK SPI Shift Clock

TIO1 Versatile Timer Channel 1

MDIDO SPI Master In Slave Out

TIO2 Versatile Timer Channel 2

UART Ready-To-Send Output

UART Clear-To-Send Input

Non-Maskable Interrupt Input

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CP3UB17

Name Pins I/O Primary Function

PH2 1 I/O Generic I/O

PH3 1 I/O Generic I/O

PH4 1 I/O Generic I/O

PH5 1 I/O Generic I/O

PH6 1 I/O Generic I/O

PH7 1 I/O Generic I/O

PI0 1 I/O Generic I/O None None

PI1 1 I/O Generic I/O None None

PI2 1 I/O Generic I/O SRCLK AAI Receive Clock

PI3 1 I/O Generic I/O None None

Alternate

Name

MDODI SPI Master Out Slave In

TIO3 Versatile Timer Channel 3

MWCS

TIO4 Versatile Timer Channel 4

SCK AAI Clock

TIO5 Versatile Timer Channel 5

SFS AAI Frame Synchronization

TIO6 Versatile Timer Channel 6

STD AAI Transmit Data Output

TIO7 Versatile Timer Channel 7

SRD AAI Receive Data Input

TIO8 Versatile Timer Channel 8

SPI Slave Select Input

Alternate Function

PI4 1 I/O Generic I/O None None

PI5 1 I/O Generic I/O None None

PI6 1 I/O Generic I/O WUI9 Multi-Input Wake-Up Channel 9

PI7 1 I/O Generic I/O TA Multi Function Timer Port A

D+ 1 I/O USB D+ Upstream Port None None

D- 1 I/O USB D- Upstream Port None None

UVCC 1 Input 3.3V USB Transceiver Supply None None

UGND 1 Input USB Transceiver Ground None None

SDA 1 I/O ACCESS.bus Serial Data None None

SCL 1 I/O ACCESS.bus Clock None None

ENV0 1 I/O

ENV1 1 I/O

Special mode select input with internal pull-up during reset

PLLCLK PLL Clock Output

CPUCLK CPU Clock Output

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5.0 CPU Architecture

The CP3UB17 uses the CR16C third-generation 16-bit CompactRISC processor core. The CPU implements a Re-

CP3UB17

duced Instruction Set Computer (RISC) architecture that allows an effective execution rate of up to one instruction per clock cycle. For a detailed description of the CPU16C architecture, see the CompactRISC CR16C Programmer’s Ref- erence Manual which is available on the National Semiconductor web site (http://www.nsc.com).

The CR16C CPU core includes these internal registers:

 General-purpose registers (R0-R13, RA, and SP)  Dedicated address registers (PC, ISP, USP, and INT-

BASE)

 Processor Status Register (PSR)  Configuration Register (CFG)

The R0-R11, PSR, and CFG registers are 16 bits wide. The R12, R13, RA, SP, ISP and USP registers are 32 bits wide. The PC register is 24 bits wide. Figure 1 shows the CPU registers.

Dedicated Address Registers

ISPH

USPH

INTBASEH

ISPL

USPL

INTBASEL

Processor Status Register

PSR

Configuration Register

CFG

Figure 1. CPU Registers

Some register bits are designated as “reserved.” Software must write a zero to these bit locations when it writes to the register. Read operations from reserved bit locations return undefined values.

5.1 GENERAL-PURPOSE REGISTERS

The CompactRISC CPU features 16 general-purpose registers. These registers are used individually as 16-bit operands or as register pairs for operations on addresses greater than 16 bits.

 General-purpose registers are defined as R0 through

R13, RA, and SP.

 Registers are grouped into pairs based on the setting of

the Short Register bit in the Configuration Register (CFG.SR). When the CFG.SR bit is set, the grouping of register pairs is upward-compatible with the architecture of the earlier CR16A/B CPU cores: (R1,R0), (R2,R1) ... (R11,R10), (R12_L, R11), (R13_L, R12_L), (R14_L, R13_L) and SP. (R14_L, R13_L) is the same as (RA,ERA).

General-Purpose Registers

15 0

R10

R11

R12

R13

DS004

 When the CFG.SR bit is clear, register pairs are grouped

in the manner used by native CR16C software: (R1,R0), (R2,R1) ... (R11,R10), (R12_L, R11), R12, R13, RA, SP. R12, R13, RA, and SP are 32-bit registers for holding addresses greater than 16 bits.

With the recommended calling convention for the architecture, some of these registers are assigned special hardware and software functions. Registers R0 to R13 are for generalpurpose use, such as holding variables, addresses, or index values. The SP register holds a pointer to the program runtime stack. The RA register holds a subroutine return address. The R12 and R13 registers are available to hold base addresses used in the index addressing mode.

If a general-purpose register is specified by an operation that is 8 bits long, only the lower byte of the register is used; the upper part is not referenced or modified. Similarly, for word operations on register pairs, only the lower word is used. The upper word is not referenced or modified.

5.2 DEDICATED ADDRESS REGISTERS

The CR16C has four dedicated address registers to implement specific functions: the PC, ISP, USP, and INTBASE registers.

5.2.1 Program Counter (PC) Register

The 24-bit value in the PC register points to the first byte of the instruction currently being executed. CR16C instructions are aligned to even addresses, therefore the least significant bit of the PC is always 0. At reset, the PC is initialized to 0 or an optional predetermined value. When a warm reset occurs, value of the PC prior to reset is saved in the (R1,R0) general-purpose register pair.

5.2.2 Interrupt Stack Pointer (ISP)

The 32-bit ISP register points to the top of the interrupt stack. This stack is used by hardware to service exceptions (interrupts and traps). The stack pointer may be accessed as the ISP register for initialization. The interrupt stack can be located anywhere in the CPU address space. The ISP cannot be used for any purpose other than the interrupt stack, which is used for automatic storage of the CPU registers when an exception occurs and restoration of these registers when the exception handler returns. The interrupt stack grows downward in memory. The least significant bit and the 8 most significant bits of the ISP register are always

5.2.3 User Stack Pointer (USP)

The USP register points to the top of the user-mode program stack. Separate stacks are available for user and supervisor modes, to support protection mechanisms for multitasking software. The processor mode is controlled by the U bit in the PSR register (which is called PSR.U in the shorthand convention). Stack grow downward in memory. If the USP register points to an illegal address (any address greater than 0x00FF_FFFF) and the USP is used for stack access, an IAD trap is taken.

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5.2.4 Interrupt Base Register (INTBASE)

The INTBASE register holds the address of the dispatch table for exceptions. The dispatch table can be located anywhere in the CPU address space. When loading the INTBASE register, bits 31 to 24 and bit 0 must written with 0.

5.3 PROCESSOR STATUS REGISTER (PSR)

The PSR provides state information and controls operating modes for the CPU. The format of the PSR is shown below.

15 12 11 10 9 8 7 6 5 4 3 2 1 0

Reserved I P E 0 N Z F 0 U L T C

C The Carry bit indicates whether a carry or bor-

row occurred after addition or subtraction. 0 – No carry or borrow occurred. 1 – Carry or borrow occurred.

T The Trace bit enables execution tracing, in

which a Trace trap (TRC) is taken after every instruction. Tracing is automatically disabled during the execution of an exception handler.

– Tracing disabled.

0 1 – Tracing enabled.

L The Low bit indicates the result of the last

comparison operation, with the operands interpreted as unsigned integers.

– Second operand greater than or equal to

first operand.

1 – Second operand less than first operand.

U The User Mode bit controls whether the CPU

is in user or supervisor mode. In supervisor mode, the SP register is used for stack operations. In user mode, the USP register is used instead. User mode is entered by executing the Jump USR instruction. When an exception is taken, the exception handler automatically begins execution in supervisor mode. The USP register is accessible using the Load Processor Register (LPR/LPRD) instruction in supervisor mode. In user mode, an attempt to access the USP register generates a UND trap.

– CPU is executing in supervisor mode.

– CPU is executing in user mode.

F The Flag bit is a general condition flag for sig-

nalling exception conditions or distinguishing the results of an instruction, among other thing uses. For example, integer arithmetic instructions use the F bit to indicate an overflow condition after an addition or subtraction operation.

Z The Zero bit is used by comparison opera-

tions. In a comparison of integers, the Z bit is set if the two operands are equal. If the operands are unequal, the Z bit is cleared.

– Source and destination operands un-

equal.

1 – Source and destination operands equal.

N The Negative bit indicates the result of the last

comparison operation, with the operands interpreted as signed integers.

– Second operand greater than or equal to

first operand.

1 – Second operand less than first operand.

E The Local Maskable Interrupt Enable bit en-

ables or disables maskable interrupts. If this bit and the Global Maskable Interrupt Enable (I) bit are both set, all interrupts are enabled. If either of these bits is clear, only the nonmaskable interrupt is enabled. The E bit is set by the Enable Interrupts (EI) instruction and cleared by the Disable Interrupts (DI) instruction.

– Maskable interrupts disabled.

0 1 – Maskable interrupts enabled.

P The Trace Trap Pending bit is used together

with the Trace (T) bit to prevent a Trace (TRC) trap from occurring more than once for one instruction. At the beginning of the execution of an instruction, the state of the T bit is copied into the P bit. If the P bit remains set at the end of the instruction execution, the TRC trap is taken.

– No trace trap pending.

– Trace trap pending.

I The Global Maskable Interrupt Enable bit is

used to enable or disable maskable interrupts. If this bit and the Local Maskable Interrupt Enable (E) bit are both set, all maskable interrupts are taken. If either bit is clear, only the non-maskable interrupt is taken. Unlike the E bit, the I bit is automatically cleared when an interrupt occurs and automatically set upon completion of an interrupt handler.

– Maskable interrupts disabled.

0 1 – Maskable interrupts enabled.

Bits Z, C, L, N, and F of the PSR are referenced from assembly language by the condition code in conditional branch instructions. A conditional branch instruction may cause a branch in program execution, based on the value of one or more of these PSR bits. For example, one of the Bcond instructions, BEQ (Branch EQual), causes a branch if the PSR.Z bit is set.

On reset, bits 0 through 11 of the PSR are cleared, except for the PSR.E bit, which is set. On warm reset, the values of each bit before reset are copied into the R2 general-purpose register. Bits 4 and 8 of the PSR have a constant value of 0. Bits 12 through 15 are reserved. In general, status bits are modified only by specific instructions. Otherwise, status bits maintain their values throughout instructions which do not implicitly affect them.

CP3UB17

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5.4 CONFIGURATION REGISTER (CFG)

The CFG register is used to enable or disable various operating modes and to control optional on-chip caches. Because the CP3UB17 does not have cache memory, the

CP3UB17

cache control bits in the CFG register are reserved. All CFG bits are cleared on reset.

15 10 9 8 7 6 5 2 1 0

Reserved SR ED 0 0 Reserved 0 0

ED The Extended Dispatch bit selects whether

the size of an entry in the interrupt dispatch table (IDT) is 16 or 32 bits. Each entry holds the address of the appropriate exception handler. When the IDT has 16-bit entries, and all exception handlers must reside in the first 128K of the address space. The location of the IDT is held in the INTBASE register, which is not affected by the state of the ED bit.

– Interrupt dispatch table has 16-bit entries.

0 1 – Interrupt dispatch table has 32-bit entries.

SR The Short Register bit enables a compatibility

mode for the CR16B large model. In the CR16C core, registers R12, R13, and RA are extended to 32 bits. In the CR16B large model, only the lower 16 bits of these registers are used, and these “short registers” are paired together for 32-bit operations. In this mode, the (RA, R13) register pair is used as the extended RA register, and address displacements relative to a single register are supported with offsets of 0 and 14 bits in place of the index addressing with these displacements.

– 32-bit registers are used.

0 1 – 16-bit registers are used (CR16B mode).

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5.5 ADDRESSING MODES

The CR16C CPU core implements a load/store architecture, in which arithmetic and logical instructions operate on register operands. Memory operands are made accessible in registers using load and store instructions. For efficient implementation of I/O-intensive embedded applications, the architecture also provides a set of bit operations that operate on memory operands.

The load and store instructions support these addressing modes: register/pair, immediate, relative, absolute, and index addressing. When register pairs are used, the lower bits are in the lower index register and the upper bits are in the higher index register. When the CFG.SR bit is clear, the 32bit registers R12, R13, RA, and SP are also treated as register pairs.

References to register pairs in assembly language use parentheses. With a register pair, the lower numbered register pair must be on the right. For example,

jump (r5, r4)

load $4(r4,r3), (r6,r5)

load $5(r12), (r13)

The instruction set supports the following addressing modes:

Immediate Mode

Relative Mode In relative mode, the operand is ad-

In register/pair mode, the operand is held in a general-purpose register, or in a general-purpose register pair. For example, the following instruction adds the contents of the low byte of register r1 to the contents of the low byte of r2, and places the result in the low byte register r2. The high byte of register r2 is not modified.

ADDB R1, R2 In immediate mode, the operand is a con-

stant value which is encoded in the instruction. For example, the following instruction multiplies the value of r4 by 4 and places the result in r4.

MULW $4, R4

dressed using a relative value (displacement) encoded in the instruction. This displacement is relative to the current Program Counter (PC), a general-purpose register, or a register pair.

In branch instructions, the displacement is always relative to the current value of the PC Register. For example, the following instruction causes an unconditional branch to an address 10 ahead of the current PC.

BR *+10

CP3UB17

In another example, the operand resides in memory. Its address is obtained by adding a displacement encoded in the instruction to the contents of register r5. The address calculation does not modify the contents of register r5.

LOADW 12(R5), R6 The following example calculates the ad-

dress of a source operand by adding a displacement of 4 to the contents of a register pair (r5, r4) and loads this operand into the register pair (r7, r6). r7 receives the high word of the operand, and r6 receives the low word.

LOADD 4(r5, r4), (r7, r6)

Index Mode In index mode, the operand address is

calculated with a base address held in either R12 or R13. The CFG.SR bit must be clear to use this mode.

 For relative mode operands, the mem-

ory address is calculated by adding the value of a register pair and a displacement to the base address. The displacement can be a 14 or 20-bit unsigned value, which is encoded in the instruction.

 For absolute mode operands, the

memory address is calculated by adding a 20-bit absolute address encoded in the instruction to the base address.

In the following example, the operand address is the sum of the displacement 4, the contents of the register pair (r5,r4), and the base address held in register r12. The word at this address is loaded into register r6.

LOADW [r12]4(r5, r4), r6

Absolute Mode In absolute mode, the operand is located

in memory, and its address is encoded in the instruction (normally 20 or 24 bits). For example, the following instruction loads the byte at address 4000 into the lower 8 bits of register r6.

LOADB 4000, r6

For additional information on the addressing modes, see the CompactRISC CR16C Programmer's Reference Manual.

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5.6 STACKS

A stack is a last-in, first-out data structure for dynamic storage of data and addresses. A stack consists of a block of memory used to hold the data and a pointer to the top of the

CP3UB17

stack. As more data is pushed onto a stack, the stack grows downward in memory. The CR16C supports two types of stacks: the interrupt stack and program stacks.

5.6.1 Interrupt Stack

The processor uses the interrupt stack to save and restore the program state during the exception handling. Hardware automatically pushes this data onto the interrupt stack before entering an exception handler. When the exception handler returns, hardware restores the processor state with data popped from the interrupt stack. The interrupt stack pointer is held in the ISP register.

5.6.2 Program Stack

The program stack is normally used by software to save and restore register values on subroutine entry and exit, hold local and temporary variables, and hold parameters passed between the calling routine and the subroutine. The only hardware mechanisms which operate on the program stack are the PUSH, POP, and POPRET instructions.

5.6.3 User and Supervisor Stack Pointers

To support multitasking operating systems, support is provided for two program stack pointers: a user stack pointer and a supervisor stack pointer. When the PSR.U bit is clear, the SP register is used for all program stack operations. This is the default mode when the user/supervisor protection mechanism is not used, and it is the supervisor mode when protection is used.

When the PSR.U bit is set, the processor is in user mode, and the USP register is used as the program stack pointer. User mode can only be entered using the JUSR instruction, which performs a jump and sets the PSR.U bit. User mode is exited when an exception is taken and re-entered when the exception handler returns. In user mode, the LPRD instruction cannot be used to change the state of processor registers (such as the PSR).

5.7 INSTRUCTION SET

Table 6 lists the operand specifiers for the instruction set, and Table 7 is a summary of all instructions. For each instruction, the table shows the mnemonic and a brief description of the operation performed.

In the mnemonic column, the lower-case letter “i” is used to indicate the type of integer that the instruction operates on, either “B” for byte or “W” for word. For example, the notation ADDi for the “add” instruction means that there are two forms of this instruction, ADDB and ADDW, which operate on bytes and words, respectively.

Similarly, the lower-case string “cond” is used to indicate the type of condition tested by the instruction. For example, the notation Jcond represents a class of conditional jump instructions: JEQ for Jump on Equal, JNE for Jump on Not Equal, etc. For detailed information on all instructions, see the CompactRISC CR16C Programmer's Reference Manu- al.

Table 6 Key to Operand Specifiers

Operand Specifier Description

abs Absolute address

disp

imm

Iposition Bit position in memory

Rbase Base register (relative mode)

Rdest Destination register

Rindex Index register

RPbase, RPbasex Base register pair (relative mode)

RPdest Destination register pair

RPlink Link register pair

Rposition Bit position in register

Displacement (numeric suffix

indicates number of bits)

Immediate operand (numeric suf-

fix indicates number of bits)

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Rproc 16-bit processor register

Rprocd 32-bit processor register

RPsrc Source register pair

RPtarget Target register pair

Rsrc, Rsrc1, Rsrc2 Source register

Table 7 Instruction Set Summary

Mnemonic Operands Description

MOVi Rsrc/imm, Rdest Move

MOVXB Rsrc, Rdest Move with sign extension

MOVZB Rsrc, Rdest Move with zero extension

MOVXW Rsrc, RPdest Move with sign extension

MOVZW Rsrc, RPdest Move with zero extension

MOVD imm, RPdest Move immediate to register-pair

RPsrc, RPdest Move between register-pairs

ADD[U]i Rsrc/imm, Rdest Add

ADDCi Rsrc/imm, Rdest Add with carry

ADDD RPsrc/imm, RPdest Add with RP or immediate.

MACQWa Rsrc1, Rsrc2, RPdest Multiply signed Q15:

RPdest := RPdest + (Rsrc1 × Rsrc2)

MACSWa Rsrc1, Rsrc2, RPdest Multiply signed and add result:

RPdest := RPdest + (Rsrc1 × Rsrc2)

CP3UB17

MACUWa Rsrc1, Rsrc2, RPdest Multiply unsigned and add result:

RPdest := RPdest + (Rsrc1 × Rsrc2)

MULi Rsrc/imm, Rdest Multiply: Rdest(8) := Rdest(8) × Rsrc(8)/imm

Rdest(16) := Rdest(16) × Rsrc(16)/imm

MULSB Rsrc, Rdest Multiply: Rdest(16) := Rdest(8) × Rsrc(8)

MULSW Rsrc, RPdest Multiply: RPdest := RPdest(16) × Rsrc(16)

MULUW Rsrc, RPdest Multiply: RPdest := RPdest(16) × Rsrc(16);

SUBi Rsrc/imm, Rdest Subtract: (Rdest := Rdest - Rsrc/imm)

SUBD RPsrc/imm, RPdest Subtract: (RPdest := RPdest - RPsrc/imm)

SUBCi Rsrc/imm, Rdest Subtract with carry: (Rdest := Rdest - Rsrc/imm)

CMPi Rsrc/imm, Rdest Compare Rdest - Rsrc/imm

CMPD RPsrc/imm, RPdest Compare RPdest - RPsrc/imm

BEQ0i Rsrc, disp Compare Rsrc to 0 and branch if EQUAL

BNE0i Rsrc, disp Compare Rsrc to 0 and branch if NOT EQUAL

ANDi Rsrc/imm, Rdest Logical AND: Rdest := Rdest & Rsrc/imm

ANDD RPsrc/imm, RPdest Logical AND: RPdest := RPsrc & RPsrc/imm

ORi Rsrc/imm, Rdest Logical OR: Rdest := Rdest | Rsrc/imm

ORD RPsrc/imm, RPdest Logical OR: Rdest := RPdest | RPsrc/imm

Scond Rdest Save condition code as boolean

XORi Rsrc/imm, Rdest Logical exclusive OR: Rdest := Rdest ^ Rsrc/imm

XORD RPsrc/imm, RPdest Logical exclusive OR: Rdest := RPdest ^ RPsrc/imm

ASHUi Rsrc/imm, Rdest Arithmetic left/right shift

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Table 7 Instruction Set Summary

Mnemonic Operands Description

CP3UB17

ASHUD Rsrc/imm, RPdest Arithmetic left/right shift

LSHi Rsrc/imm, Rdest Logical left/right shift

LSHD Rsrc/imm, RPdest Logical left/right shift

SBITi Iposition, disp(Rbase) Set a bit in memory

Iposition, disp(RPbase)

Iposition, (Rindex)disp(RPbasex)

Iposition, abs

Iposition, (Rindex)abs

CBITi Iposition, disp(Rbase) Clear a bit in memory

Iposition, disp(RPbase)

Iposition, (Rindex)disp(RPbasex)

Iposition, abs

Iposition, (Rindex)abs

(Because this instruction treats the destination as a readmodify-write operand, it not be used to set bits in writeonly registers.)

TBIT TBITi

LPR Rsrc, Rproc Load processor register

LPRD RPsrc, Rprocd Load double processor register

SPR Rproc, Rdest Store processor register

SPRD Rprocd, RPdest Store 32-bit processor register

Bcond disp9 Conditional branch

BAL RPlink, disp24 Branch and link

BR disp9 Branch

Rposition/imm, Rsrc Test a bit in a register

Iposition, disp(Rbase)

Iposition, disp(RPbase)

Iposition, (Rindex)disp(RPbasex)

Iposition, abs

Iposition, (Rindex)abs

disp17

disp24

disp17

disp24

Test a bit in memory

EXCP vector Trap (vector)

Jcond RPtarget Conditional Jump to a large address

JAL RA, RPtarget, Jump and link to a large address

RPlink, RPtarget

JUMP RPtarget Jump

JUSR RPtarget Jump and set PSR.U

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Table 7 Instruction Set Summary

Mnemonic Operands Description

RETX Return from exception

PUSH imm, Rsrc, RA Push “imm” number of registers on user stack, starting

with Rsrc and possibly including RA

POP imm, Rdest, RA Restore “imm” number of registers from user stack,

starting with Rdest and possibly including RA

POPRET imm, Rdest, RA Restore registers (similar to POP) and JUMP RA

LOADi disp(Rbase), Rdest Load (register relative)

abs, Rdest Load (absolute)

(Rindex)abs, Rdest Load (absolute index relative)

(Rindex)disp(RPbasex), Rdest Load (register relative index)

disp(RPbase), Rdest Load (register pair relative)

LOADD disp(Rbase), Rdest Load (register relative)

abs, Rdest Load (absolute)

(Rindex)abs, Rdest Load (absolute index relative)

CP3UB17

(Rindex)disp(RPbasex), Rdest Load (register pair relative index)

disp(RPbase), Rdest Load (register pair relative)

STORi Rsrc, disp(Rbase) Store (register relative)

Rsrc, disp(RPbase) Store (register pair relative)

Rsrc, abs Store (absolute)

Rsrc, (Rindex)disp(RPbasex) Store (register pair relative index)

Rsrc, (Rindex)abs Store (absolute index)

STORD RPsrc, disp(Rbase) Store (register relative)

RPsrc, disp(RPbase) Store (register pair relative)

RPsrc, abs Store (absolute)

RPsrc, (Rindex)disp(RPbasex) Store (register pair index relative)

RPsrc, (Rindex)abs Store (absolute index relative)

STOR IMM imm4, disp(Rbase) Store unsigned 4-bit immediate value extended to operand

imm4, disp(RPbase)

imm4, (Rindex)disp(RPbasex)

imm4, abs

imm4, (Rindex)abs

length in memory

LOADM imm3 Load 1 to 8 registers (R2-R5, R8-R11) from memory

starting at (R0)

LOADMP imm3 Load 1 to 8 registers (R2-R5, R8-R11) from memory

starting at (R1, R0)

STORM STORM imm3 Store 1 to 8 registers (R2-R5, R8-R11) to memory starting

at (R2)

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Table 7 Instruction Set Summary

Mnemonic Operands Description

CP3UB17

STORMP imm3 Store 1 to 8 registers (R2-R5, R8-R11) to memory starting

at (R7,R6)

DI Disable maskable interrupts

EI Enable maskable interrupts

EIWAIT Enable maskable interrupts and wait for interrupt

NOP No operation

WAIT Wait for interrupt

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6.0 Memory

The CP3UB17 supports a uniform 16M-byte linear address space. Table 8 lists the types of memory and peripherals that occupy this memory space. Unlisted address ranges

Table 8 CP3UB17 Memory Map

CP3UB17

are reserved and must not be read or written. The BIU zones are regions of the address space that share the same control bits in the Bus Interface Unit (BIU).

Start

Address

00 0000h 03 FFFFh 256K

04 0000h 0D FFFFh 640K Reserved

0E 0000h 0E 1FFFh 8K On-chip Flash Data Memory

0E 2000h 0E 7FFFh 24K Reserved

0E 8000h 0E 91FFh 4.5K Reserved N/A

0E 9200h 0E BFFFh 11.5K Reserved

0E C000h 0E E7FFh 10K System RAM

0E E800h 0E EBFFh 1K Reserved

0E EC00h 0E EFFFh 1K Reserved

0E F000h 0E F13Fh 320 Reserved

0E F140h 0E F17Fh 64 Reserved

0E F180h 0E F1FFh 128 Reserved

0E F200h 0F FFFFh 67.5K Reserved

10 0000h 3F FFFFh 3072K Reserved

End

Address

Size in

Bytes

Description BIU Zone

On-chip Flash Program Memory, including Boot Memory

Static Zone 0 (mapped internally in IRE and ERE mode; mapped to the external bus in DEV mode)

40 0000h 7F FFFFh 4096K External Memory Zone 1 Static Zone 1

80 0000h FE FFFFh 8128K External Memory Zone 2 Static Zone 2

FF 0000h FF FAFFh 64256 BIU Peripherals

FF FB00h FF FBFFh 256 I/O Expansion I/O Zone

FF FC00h FF FFFFh 1K Peripherals and Other I/O Ports N/A

6.1 OPERATING ENVIRONMENT

The operating environment controls whether external memory is supported and whether the reset vector jumps to a code space intended to support In-System Programming (ISP). Up to 8M of external memory space is available.

The operating mode of the device is controlled by the states on the ENV2:0 pins at reset, as shown in Table 9.

Table 9 Operating Environment Selection

ENV2:0 Operating Environment

When ENV2:0 = 111, IRE mode is selected unless the EMPTY bits in the Protection word indicate that the program flash memory is empty (unprogrammed), in which case ISP mode is selected. See Section 8.4.2 for more details. The ENV2 pin is only available on the 100-pin packages, therefore it is not possible to enter the ERE or DEV environments on the 48-pin versions of the CP3UB17.

In the DEV environment, the on-chip flash memory is disabled, and the corresponding region of the address space is mapped to external memory.

6.2 BUS INTERFACE UNIT (BIU)

x10 In-System-Programming (ISP) mode

111 Internal ROM enabled (IRE) or ISP mode

011 External ROM enabled (ERE) mode

000 Development (DEV) mode

Internal pullups on the ENV2:0 pins select IRE mode or ISP mode if these pins are allowed to float.

The BIU controls the interface between the CPU core bus and those on-chip modules which are mapped into BIU zones. These on-chip modules are the flash program memory and the I/O zone. The BIU controls the configured parameters for bus access (such as the number of wait states for memory access) and issues the appropriate bus signals for the requested access.

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6.3 BUS CYCLES

There are four types of data transfer bus cycles:

 Normal read

CP3UB17

 Fast read  Early write  Late write

The type of data cycle used in a particular transaction depends on the type of CPU operation (a write or a read), the type of memory or I/O being accessed, and the access type programmed into the BIU control registers (early/late write or normal/fast read).

For read operations, a basic normal read takes two clock cycles, and a fast-read bus cycle takes one clock cycle. Normal read bus cycles are enabled by default after reset.

For write operations, a basic late-write bus cycle takes two clock cycles, and a basic early-write bus cycle takes three clock cycles. Early-write bus cycles are enabled by default after reset. However, late-write bus cycles are needed for ordinary write operations, so this configuration must be changed by software (see Section 6.4.1).

In certain cases, one or more additional clock cycles are added to a bus access cycle. There are two types of additional clock cycles for ordinary memory accesses, called internal wait cycles (TIW) and hold (T

A wait cycle is inserted in a bus cycle just after the memory address has been placed on the address bus. This gives the accessed memory more time to respond to the transaction request.

A hold cycle is inserted at the end of a bus cycle. This holds the data on the data bus for an extended number of clock cycles.

hold

) cycles.

6.4 BIU CONTROL REGISTERS

The BIU has a set of control registers that determine how many wait cycles and hold cycles are to be used for accessing memory. During initialization of the system, these registers should be programmed with appropriate values so that the minimum allowable number of cycles is used. This number varies with the clock frequency.

There are five BIU control registers, as listed in Table 10. These registers control the bus cycle configuration used for accessing the various on-chip memory types.

Table 10 Bus Control Registers

Name Address Description

BCFG FF F900h BIU Configuration Register

IOCFG FF F902h

SZCFG0 FF F904h

SZCFG1 FF F906h

SZCFG2 FF F908h

I/O Zone Configuration

Static Zone 0

Configuration Register

Static Zone 1

Configuration Register

Static Zone 2

Configuration Register

6.4.1 BIU Configuration Register (BCFG)

The BCFG register is a byte-wide, read/write register that selects early-write or late-write bus cycles. At reset, the register is initialized to 07h. The register format is shown below.

7 3 2 1 0

Reserved 1 1 EWR

EWR The Early Write bit controls write cycle timing.

– Late-write operation (2 clock cycles to

write).

– Early-write operation.

At reset, the BCFG register is initialized to 07h, which selects early-write operation. However, late-write operation is required for normal device operation, so software must change the register value to 06h. Bits 1 and 2 of this register must always be set when writing to this register.

6.4.2 I/O Zone Configuration Register (IOCFG)

The IOCFG register is a word-wide, read/write register that controls the timing and bus characteristics of accesses to the 256-byte I/O Zone memory space (FF FB00h to FF FBFFh). The registers associated with Port B and Port C reside in the I/O memory array. At reset, the register is initialized to 069Fh. The register format is shown below.

7 6 5 4 3 2 0

BW Reserved HOLD WAIT

15 10 9 8

Reserved IPST Res.

WAIT The Memory Wait Cycles field specifies the

number of TIW (internal wait state) clock cycles added for each memory access, ranging from 000 binary for no additional TIW wait cycles to 111 binary for seven additional TIW wait cycles.

HOLD The Memory Hold Cycles field specifies the

number of T memory access, ranging from 00b for no T

cycles to 11b for three T

hold

cles.

BW The Bus Width bit defines the bus width of the

IO Zone.

– 8-bit bus width.

– 16-bit bus width (default)

IPST The Post Idle bit controls whether an idle cycle

follows the current bus cycle, when the next bus cycle accesses a different zone. No idle cycles are required for on-chip accesses.

– No idle cycle (recommended).

– Idle cycle.

clock cycles used for each

hold

clock cy-

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6.4.3 Static Zone 0 Configuration Register (SZCFG0)

The SZCFG0 register is a word-wide, read/write register that controls the timing and bus characteristics of Zone 0 memory accesses. Zone 0 is used for the on-chip flash memory (including the boot area, program memory, and data memory).

At reset, the register is initialized to 069Fh. The register format is shown below.

7 6 5 4 3 2 0

BW WBR RBE HOLD WAIT

15 12 11 10 9 8

Reserved FRE IPRE IPST Res.

WAIT The Memory Wait field specifies the number

of TIW (internal wait state) clock cycles added for each memory access, ranging from 000b for no additional TIW wait cycles to 111b for seven additional TIW wait cycles. These bits are ignored if the SZCFG0.FRE bit is set.

HOLD The Memory Hold field specifies the number

of T access, ranging from 00b for no T to 11b for three T are ignored if the SZCFG0.FRE bit is set.

RBE The Read Burst Enable enables burst cycles

on 16-bit reads from 8-bit bus width regions of the address space. Because the flash program memory is required to be 16-bit bus width, the RBE bit is a don’t care bit. This bit is ignored when the SZCFG0.FRE bit is set. 0 1 – Burst read enabled.

WBR The Wait on Burst Read bit controls if a wait

state is added on burst read transaction. This bit is ignored, when SZCFG0.FRE bit is set or when SZCFG0.RBE is clear. 0 1 – One TBW on burst read cycles.

BW The Bus Width bit controls the bus width of the

zone. The flash program memory must be configured for 16-bit bus width. 0 1

FRE The Fast Read Enable bit controls whether

fast read bus cycles are used. A fast read operation takes one clock cycle. A normal read operation takes at least two clock cycles. 0 1

IPST The Post Idle bit controls whether an idle cycle

follows the current bus cycle, when the next bus cycle accesses a different zone. No idle cycles are required for on-chip accesses. 0 1

clock cycles used for each memory

hold

clock cycles. These bits

hold

– Burst read disabled.

– No TBW on burst read cycles.

– 8-bit bus width. – 16-bit bus width (required).

– Normal read cycles. – Fast read cycles.

– No idle cycle (recommended). – Idle cycle inserted.

hold

cycles

IPRE The Preliminary Idle bit controls whether an

idle cycle is inserted prior to the current bus cycle, when the new bus cycle accesses a different zone. No idle cycles are required for onchip accesses.

– No idle cycle (recommended).

– Idle cycle inserted.

6.4.4 Static Zone 1 Configuration Register (SZCFG1)

The SZCFG1 register is a word-wide, read/write register that controls the timing and bus characteristics for off-chip accesses selected with the SEL1

At reset, the register is initialized to 069Fh. The register format is shown below.

7 6 5 4 3 2 0

BW WBR RBE HOLD WAIT

15 12 11 10 9 8

Reserved FRE IPRE IPST Res.

WAIT The Memory Wait field specifies the number

HOLD The Memory Hold field specifies the number

of T access, ranging from 00b for no T to 11b for three T are ignored if the SZCFG1.FRE bit is set.

RBE The Read Burst Enable enables burst cycles

on 16-bit reads from 8-bit bus width regions of the address space. This bit is ignored when the SZCFG1.FRE bit is set or the SZCFG1.BW is clear. 0 1

WBR The Wait on Burst Read bit controls if a wait

state is added on burst read transaction. This bit is ignored, when SZCFG1.FRE bit is set or when SZCFG1.RBE is clear. 0 1

BW The Bus Width bit controls the bus width of the

zone. 0 1

FRE The Fast Read Enable bit controls whether

fast read bus cycles are used. A fast read operation takes one clock cycle. A normal read operation takes at least two clock cycles. 0 1

clock cycles used for each memory

hold

– Burst read disabled. – Burst read enabled.

– No TBW on burst read cycles. – One TBW on burst read cycles.

– 8-bit bus width. – 16-bit bus width.

– Normal read cycles. – Fast read cycles.

output signal.

clock cycles. These bits

hold

cycles

CP3UB17

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IPST The Post Idle bit controls whether an idle cycle

follows the current bus cycle, when the next bus cycle accesses a different zone.

– No idle cycle.

CP3UB17

IPRE The Preliminary Idle bit controls whether an

6.4.5 Static Zone 2 Configuration Register (SZCFG2)

The SZCFG2 register is a word-wide, read/write register that controls the timing and bus characteristics for off-chip accesses selected with the SEL2 output signal.

At reset, the register is initialized to 069Fh. The register format is shown below.

7 6 5 4 3 2 0

BW WBR RBE HOLD WAIT

0 1 – Idle cycle inserted.

idle cycle is inserted prior to the current bus cycle, when the new bus cycle accesses a different zone.

– No idle cycle.

0 1

– Idle cycle inserted.

FRE The Fast Read Enable bit controls whether

fast read bus cycles are used. A fast read operation takes one clock cycle. A normal read operation takes at least two clock cycles.

– Normal read cycles.

0 1 – Fast read cycles.

IPST The Post Idle bit controls whether an idle cycle

follows the current bus cycle, when the next bus cycle accesses a different zone.

– No idle cycle.

0 1

– Idle cycle inserted.

IPRE The Preliminary Idle bit controls whether an

idle cycle is inserted prior to the current bus cycle, when the new bus cycle accesses a different zone.

– No idle cycle.

0 1 – Idle cycle inserted.

6.5 WAIT AND HOLD STATES

The number of wait cycles and hold cycles inserted into a bus cycle depends on whether it is a read or write operation, the type of memory or I/O being accessed, and the control register settings.

15 12 11 10 9 8

Reserved FRE IPRE IPST Res.

WAIT The Memory Wait field specifies the number

HOLD The Memory Hold field specifies the number

of T access, ranging from 00b for no T to 11b for three T are ignored if the SZCFG2.FRE bit is set.

RBE The Read Burst Enable enables burst cycles

on 16-bit reads from 8-bit bus width regions of the address space. This bit is ignored when the SZCFG2.FRE bit is set or the SZCFG2.BW is clear. 0 1

WBR The Wait on Burst Read bit controls if a wait

state is added on burst read transaction. This bit is ignored, when SZCFG2.FRE bit is set or when SZCFG2.RBE is clear. 0 1

BW The Bus Width bit controls the bus width of the

zone. 0 1

clock cycles used for each memory

hold

clock cycles. These bits

hold

– Burst read disabled. – Burst read enabled.

– No TBW on burst read cycles. – One TBW on burst read cycles.

– 8-bit bus width. – 16-bit bus width.

hold

cycles

6.5.1 Flash Program/Data Memory

When the CPU accesses the Flash program and data memory (address ranges 000000h 0E1FFFh), the number of added wait and hold cycles depends on the type of access and the BIU register settings.

In fast-read mode (SZCFG0.FRE=1), a read operation is a single cycle access. This limits the maximum CPU operating frequency to 24 MHz.

For a read operation in normal-read mode (SZCFG0.FRE=0), the number of inserted wait cycles is specified in the SZCFG0.WAIT field. The total number of wait cycles is the value in the WAIT field plus 1, so it can range from 1 to 8. The number of inserted hold cycles is specified in the SCCFG0.HOLD field, which can range from 0 to 3.

For a write operation in fast read mode (SZCFG0.FRE=1), the number of inserted wait cycles is 1. No hold cycles are used.

For a write operation normal read mode (SZCFG0.FRE=0), the number of wait cycles is equal to the value written to the SZCFG0.WAIT field plus 1 (in the late write mode) or 2 (in the early write mode). The number of inserted hold cycles is equal to the value written to the SCCFG0.HOLD field, which can range from 0 to 3.

6.5.2 RAM Memory

Read and write accesses to on-chip RAM is performed within a single cycle, without regard to the BIU settings. The RAM address is in the range of 0E 8000h C000h–0E EBFFh.

6.5.3 Access to Peripherals

When the CPU accesses on-chip peripherals in the range of 0E F000h–0E F1FFh and FF 0000h–FF FBFFh, one wait cycle and one preliminary idle cycle is used. No hold cycles are used. The IOCFG register determines the access timing for the address range FF FB00h

–03FFFFh and 0E0000h–

–0E 91FFh and 0E

–FF FBFFh.

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7.0 System Configuration Registers

The system configuration registers control and provide status for certain aspects of device setup and operation, such as indicating the states sampled from the ENV[2:0] inputs. The system configuration registers are listed in Table 11.

Table 11 System Configuration Registers

Name Address Description

MCFG FF F910h

MSTAT FF F914h

7.1 MODULE CONFIGURATION REGISTER (MCFG)

The MCFG register is a byte-wide, read/write register that selects the clock output features of the device.

The register must be written in active mode only, not in power save, HALT, or IDLE mode. However, the register contents are preserved during all power modes.

The MCFG register format is shown below.

Module Configuration

Module Status

MISC_IO_SPEED

MEM_IO_SPEED

The MISC_IO_SPEED bit controls the slew rate of the output drivers for the ENV[2:0],

, RFDATA, and TDO pins. To minimize

RDY noise, the slow slew rate is recommended.

– Fast slew rate.

0 1 – Slow slew rate. The MEM_IO_SPEED bit controls the slew rate of the output drivers for the A[21:0], RD SEL[2:1] for the CP3UB17 are characterized with fast slew rate. Slow slew rate reduces the available memory access time by 5 ns. 0 1 – Slow slew rate.

, and WR[1:0] pins. Memory speeds

– Fast slew rate.

7.2 MODULE STATUS REGISTER (MSTAT)

The MSTAT register is a byte-wide, read-only register that indicates the general status of the device. The MSTAT register format is shown below.

7 5 4 3 2 1 0

Reserved DPGMBUSY

PGMBUSY

OENV2 OENV1 OENV0

CP3UB17

7 6 5 4 3 2 1 0

MEM_IO

Res.

_SPEED

EXIOE The EXIOE bit controls whether the external

PLLCLKOE

MCLKOE The MCLKOE bit controls whether the Main

SCLKOE The SCLKOE bit controls whether the Slow

USB_ENABLE

MISC_IO

_SPEED

bus is enabled in the IRE environment for implementing the I/O Zone (FF FB00h FBFFh).

– External bus disabled.

0 1 – External bus enabled. The PLLCLKOE bit controls whether the PLL clock is driven on the ENV0/PLLCLK pin. 0 – ENV0/PLLCLK pin is high impedance.

– PLL clock driven on ENV0/PLLCLK.

Clock is driven on the ENV1/CPUCLK pin.

– ENV1/CPUCLK pin is high impedance.

0 1 – Main Clock is driven on ENV1/CPUCLK.

Clock is driven on the ENV2/SLOWCLK pin.

– ENV2/SLOWCLK pin is high impedance.

– Slow Clock driven on ENV2/SLOWCLK.

1 The USB_ENABLE bit can be used to force an external USB transceiver into its low-power mode. The power mode is dependent on the USB controller status, the USB_ENABLE bit in the Function Word (see Section 8.4.1), and the USB_ENABLE bit in the MCFG register.

– External USB transceiver forced into low-

power mode.

– Transceiver power mode dependent on

USB controller status and programming of the Function Word. (This is the state of the USB_ENABLE bit after reset.)

USB

_ENABLE

SCLKOEMCLKOEPLLCLKOEEXI

–FF

OENV[2:0] The Operating Environment bits hold the

states sampled from the ENV[2:0] input pins at reset. These states are controlled by external hardware at reset and are held constant in the register until the next reset.

PGMBUSY The Flash Programming Busy bit is automati-

cally set when either the program memory or the data memory is being programmed or erased. It is clear when neither of the memories is busy. When this bit is set, software must not attempt to program or erase either of these two memories. This bit is a copy of the FMBUSY bit in the FMSTAT register.

– Flash memory is not busy.

– Flash memory is busy.

DPGMBUSY

The Data Flash Programming Busy indicates that the flash data memory is being erased or a pipelined programming sequence is currently ongoing. Software must not attempt to perform any write access to the flash program memory at this time, without also polling the FSMSTAT.FMFULL bit in the flash memory interface. The DPGMBUSY bit is a copy of the FMBUSY bit in the FSMSTAT register.

– Flash data memory is not busy.

0 1

– Flash data memory is busy.

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8.0 Flash Memory

The flash memory consists of the flash program memory and the flash data memory. The flash program memory is

CP3UB17

further divided into the Boot Area and the Code Area.

A special protection scheme is applied to the lower portion of the flash program memory, called the Boot Area. The Boot Area always starts at address 0 and ranges up to a programmable end address. The maximum boot area address which can be selected is 00 1BFFh. The intended use of this area is to hold In-System-Programming (ISP) routines or essential application routines. The Boot Area is always protected against CPU write access, to avoid unintended modifications.

The Code Area is intended to hold the application code and constant data. The Code Area begins with the next byte after the Boot Area. Table 12 summarizes the properties of the regions of flash memory mapped into the CPU address space.

Table 12 Flash Memory Areas

Area Address Range

Boot

Area

Code

Area

Data Area

–BOOTAREA - 1 Yes No

BOOTAREA

FFFFh

0E 0000h

–03

–0E 1FFFh Yes

8.1 FLASH MEMORY PROTECTION

The memory protection mechanisms provide both global and section-level protection. Section-level protection against CPU writes is applied to individual 8K-byte sections of the flash program memory and 512-byte sections of the flash data memory. Section-level protection is controlled through read/write registers mapped into the CPU address space. Global write protection is applied at the device level, to disable flash memory writes by the CPU. Global write protection is controlled by the encoding of bits stored in the flash memory array.

8.1.1 Section-Level Protection

Each bit in the Flash Memory Write Enable (FM0WER and FM1WER) registers enables or disables write access to a corresponding section of flash program memory. Write access to the flash data memory is controlled by the bits in the Flash Slave Memory Write Enable (FSM0WER) register. By

Read

Access

Ye s

Write Access

Write access

only if section

write enable

bit is set and

global write

protection is

disabled.

Write access

only if section

write enable

bit is set and

global write

protection is

disabled.

default (after reset) all bits in the FM0WER, FM1WER, and FSM0WER registers are cleared, which disables write access by the CPU to all sections. Write access to a section is enabled by setting the corresponding write enable bit. After completing a programming or erase operation, software should clear all write enable bits to protect the flash program memory against any unintended writes.

8.1.2 Global Protection

The WRPROT field in the Protection Word controls global write protection. The Protection Word is located in a special flash memory outside of the CPU address space. If a majority of the bits in the 3-bit WRPROT field are clear, write protection is enabled. Enabling this mode prevents the CPU from writing to flash memory.

The RDPROT field in the Protection Word controls global read protection. If a majority of the bits in the 3-bit RDPROT field are clear, read protection is enabled. Enabling this mode prevents reading by an external debugger through the serial debug interface or by an external flash programmer. CPU read access is not affected by the RDPROT bits.

8.2 FLASH MEMORY ORGANIZATION

Each of the flash memories are divided into main blocks and information blocks. The main blocks hold the code or data used by application software. The information blocks hold factory parameters, protection settings, and other devicespecific data. The main blocks are mapped into the CPU address space. The information blocks are accessed indirectly through a register-based interface. Separate sets of registers are provided for accessing flash program memory (FM registers) and flash data memory (FSM registers). The flash program memory consists of two main blocks and two data blocks, as shown in Table 13. The flash data memory consists of one main block and one information block.

Table 13 Flash Memory Blocks

Name Address Range Function

Main Block 0

Information

Block 0

Main Block 1

Information

Block 1

Main Block 2

Information

Block 2

8.2.1 Main Block 0 and 1

Main Block 0 and Main Block 1 hold the 256K-byte program space, which consists of the Boot Area and Code Area.

00 0000h

(CPU address space)

(address register)

02 0000h

(CPU address space)

(address register)

0E 0000h

(CPU address space)

(address register)

000h

080h

000h

–01 FFFFh

–07Fh

–03 FFFFh

–0FFh

–0E 1FFFh

–07Fh

Flash Program

Memory

Function Word,

Factory

Parameters

Flash Program

Memory

Protection Word,

User Data

Flash Data

Memory

User Data

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