CHAPTER 1
GUIDE TO THIS MANUAL
This manual describes the 8XC196EA embedded microcontroller. It is intended for use by both software and hardware designers familiar with the principles of microcontrollers. This chapter describes what you’ll find in this manual, lists other documents that may be useful, and explains how to access the support services we provide to help you complete your design.
1.1MANUAL CONTENTS
This manual contains several chapters and appendixes, a glossary, and an index. This chapter, Chapter 1, provides an overview of the manual. This section summarizes the contents of the remaining chapters and appendixes. The remainder of this chapter describes notational conventions and terminology used throughout the manual, provides references to related documentation, describes customer support services, and explains how to access information and assistance.
Chapter 2 — Architectural Overview provides an overview of the device hardware. It describes the core, internal timing, internal peripherals, and special operating modes. It also describes the chip configuration bytes (CCBs) and the chip configuration registers (CCRs), which control many aspects of the microcontroller’s operation.
Chapter 3 — Programming Considerations — provides an overview of the instruction set, describes general standards and conventions, and defines the operand types and addressing modes supported by the MCS® 96 microcontroller family. (For additional information about the instruction set, see Appendix A.)
Chapter 4 — Memory Partitions — describes the address space of the device. It describes the address partitions, explains how to use windows to increase the amount of memory that can be accessed with direct addressing, and lists all special-function registers (SFRs) with their addresses, and describes options for ROM protection and addressing.
Chapter 5 — Stack Overflow Module — describes the stack overflow module, the 8XC196EA peripheral that monitors the value of the stack pointer (SP) and generates a nonmaskable interrupt request if the value is outside specified boundaries.
Chapter 6 — Standard and PTS Interrupts — describes the interrupt control circuitry, priority scheme, and timing for standard and peripheral transaction server (PTS) interrupts. It also explains interrupt programming and control.
Chapter 7 — I/O Ports — describes the input/output ports and explains how to configure the pins for general-purpose input/output or for special functions.
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8XC196EA USER’S MANUAL
Chapter 8 — Serial I/O (SIO) Port — describes the asynchronous/synchronous serial I/O (SIO) port and explains how to program it.
Chapter 9 — Synchronous Serial I/O (SSIO) Port — |
describes the synchronous serial I/O |
(SSIO) port and explains how to program it. |
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Chapter 10 — Pulse-width Modulator — provides a functional overview of the pulse width modulator (PWM) modules, describes how to program them, and provides sample circuitry for converting the PWM outputs to analog signals.
Chapter 11 — Event Processor Array (EPA) — describes the event processor array, a tim- er/counter-based, high-speed input/output unit. It describes the timer/counters and explains how to program the EPA and how to use the EPA to produce pulse-width modulated (PWM) outputs.
Chapter 12 — Analog-to-digital (A/D) Converter — provides an overview of the analog-to- digital (A/D) converter and describes how to program the converter, read the conversion results, and interface with external circuitry.
Chapter 13 — Minimum Hardware Considerations — describes options for providing the basic requirements for device operation within a system, discusses other hardware considerations, and describes device reset options.
Chapter 14 — Special Operating Modes — provides an overview of the idle, powerdown, and on-circuit emulation (ONCE) modes and describes how to enter and exit each mode.
Chapter 15 — Interfacing with External Memory — lists the signals and registers used for interfacing to external devices. It discusses the bus width and memory configurations, the bushold protocol, write-control modes, and internal wait states and ready control. Finally, it provides timing information for the system bus.
Chapter 16 — Serial Debug Unit — describes the module that allows read and write access to the 3-Kbyte code/data RAM to aid in code development and debugging.
Chapter 17 — Using the Test-ROM Routines — describes the three test-ROM routines. It provides recommended circuits and the corresponding memory maps, and it defines the reduced instruction set monitor (RISM) commands.
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GUIDE TO THIS MANUAL
Appendix A — Instruction Set Reference — provides reference information for the instruction set. It describes each instruction; defines the processor status word (PSW) flags; shows the relationships between instructions and PSW flags; and lists hexadecimal opcodes, instruction lengths, and execution times. (For additional information about the instruction set, see Chapter 3, “Programming Considerations.”)
Appendix B — Signal Descriptions — provides reference information for the device pins, including descriptions of the pin functions, reset status of the I/O and control pins, and package pin assignments.
Appendix C — Registers — provides a compilation of all special-function registers (SFRs), arranged alphabetically by register mnemonic. It also includes tables that list the windowed direct addresses for all SFRs in each possible window.
Glossary — defines terms with special meaning used throughout this manual.
Index — lists key topics with page number references.
1.2NOTATIONAL CONVENTIONS AND TERMINOLOGY
The following notations and terminology are used throughout this manual. The Glossary defines other terms with special meanings.
# |
The pound symbol (#) has either of two meanings, depending on the |
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context. When used with a signal name, the symbol means that the |
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signal is active low. When used in an instruction, the symbol prefixes |
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an immediate value in immediate addressing mode. |
addresses |
In this manual, both internal and external addresses use the number |
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of hexadecimal digits that correspond with the number of available |
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address bits. |
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When writing code, use the appropriate address conventions for the |
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software tool you are using. (In general, assemblers require a zero |
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preceding an alphabetic hexadecimal character and an “H” following |
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any hexadecimal value, so FFFFFFH must be written as 0FFFFFFH. |
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ANSI ‘C’ compilers require a zero plus an “x” preceding a |
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hexadecimal value, so FFFFFFH must be written as 0xFFFFFF.) |
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Consult the manual for your assembler or compiler to determine its |
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specific requirements. |
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8XC196EA USER’S MANUAL
assert and deassert |
The terms assert and deassert refer to the act of making a signal |
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active (enabled) and inactive (disabled), respectively. The active |
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polarity (low or high) is defined by the signal name. Active-low |
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signals are designated by a pound symbol (#) suffix; active-high |
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signals have no suffix. To assert RD# is to drive it low; to assert ALE |
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is to drive it high; to deassert RD# is to drive it high; to deassert ALE |
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is to drive it low. |
clear and set |
The terms clear and set refer to the value of a bit or the act of giving |
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it a value. If a bit is clear, its value is “0”; clearing a bit gives it a “0” |
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value. If a bit is set, its value is “1”; setting a bit gives it a “1” value. |
f |
Lowercase “f” represents the internal operating frequency. See |
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“Internal Timing” on page 2-9 for details. |
instructions |
Instruction mnemonics are shown in upper case to avoid confusion. |
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In general, you may use either upper case or lower case when |
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programming. Consult the manual for your assembler or compiler to |
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determine its specific requirements. |
italics |
Italics identify variables and introduce new terminology. The context |
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in which italics are used distinguishes between the two possible |
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meanings. |
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Variables in registers and signal names are commonly represented by |
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x and y, where x represents the first variable and y represents the |
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second variable. For example, in register Px_MODE.y, x represents |
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the variable that identifies the specific port associated with the |
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register, and y represents the register bit variable (7:0 or 15:0). |
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Variables must be replaced with the correct values when configuring |
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or programming registers or identifying signals. |
numbers |
Hexadecimal numbers are represented by a string of hexadecimal |
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digits followed by the character H. Decimal and binary numbers are |
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represented by their customary notations. (That is, 255 is a decimal |
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number and 1111 1111 is a binary number. In some cases, the letter B |
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is appended to binary numbers for clarity.) |
register bits |
Bit locations are indexed by 7:0 (or 15:0), where bit 0 is the least- |
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significant bit and bit 7 (or 15) is the most-significant bit. An |
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individual bit is represented by the register name, followed by a |
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period and the bit number. For example, WSR.7 is bit 7 of the |
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window selection register. In some discussions, bit names are used. |
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GUIDE TO THIS MANUAL |
register names |
Register mnemonics are shown in upper case. For example, TIMER2 |
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is the timer 2 register; timer 2 is the timer. A register name |
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containing a lowercase italic character represents more than one |
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register. For example, the x in Px_REG indicates that the register |
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name refers to any of the port data registers. |
reserved bits |
Certain bits are described as reserved bits. In illustrations, reserved |
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bits are indicated with a dash (—). These bits are not used in this |
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device, but they may be used in future implementations. To help |
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ensure that a current software design is compatible with future imple- |
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mentations, reserved bits should be cleared (given a value of “0”) or |
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left in their default states, unless otherwise noted. Do not rely on the |
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values of reserved bits; consider them undefined. |
reserved registers |
Certain special-function register (SFR) locations are described as |
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reserved. These locations are not used in this microcontroller, but |
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they may be used in future implementations. To help ensure that a |
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current software design is compatible with future implementations, |
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do not use these locations. |
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Some special-function register (SFR) locations are described as |
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reserved for Intel. These locations are reserved for Intel’s testing. |
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Using these locations can cause unpredictable or undesirable results. |
signal names |
Signal names are shown in upper case. When several signals share a |
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common name, an individual signal is represented by the signal name |
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followed by a number. For example, the EPA signals are named |
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EPA0, EPA1, EPA2, etc. Port pins are represented by the port abbre- |
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viation, a period, and the pin number (e.g., P2.0, P2.1); a range of |
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pins is represented by Px.y:z (e.g., P2.4:0 represents five port pins: |
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P2.4, P2.3, P2.2, P2.1, P2.0). A pound symbol (#) appended to a |
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signal name identifies an active-low signal. |
t |
Lowercase “t” represents the internal operating period. See “Internal |
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Timing” on page 2-9 for details. |
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8XC196EA USER’S MANUAL
units of measure |
The following abbreviations are used to represent units of measure: |
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A |
amps, amperes |
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DCV |
direct current volts |
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Kbytes |
kilobytes |
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kHz |
kilohertz |
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kΩ |
kilo-ohms |
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mA |
milliamps, milliamperes |
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Mbytes |
megabytes |
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MHz |
megahertz |
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ms |
milliseconds |
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mW |
milliwatts |
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ns |
nanoseconds |
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pF |
picofarads |
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W |
watts |
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V |
volts |
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μA |
microamps, microamperes |
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μF |
microfarads |
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μs |
microseconds |
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μW |
microwatts |
x |
Lowercase x (italic) represents a variable. Variables must be replaced |
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with the correct values when configuring or programming registers |
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or identifying signals. |
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X |
Uppercase X (no italics) represents an unknown value or an |
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irrelevant (“don’t care”) state or condition. The value may be either |
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binary or hexadecimal, depending on the context. For example, |
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2XAFH (hex) indicates that bits 11:8 are unknown; 10XXB (binary) |
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indicates that the two least-significant bits are unknown. |
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y |
Lowercase y (italic) represents a variable. Variables must be replaced |
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with the correct values when configuring or programming registers |
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or identifying signals. |
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