Microcontrollers and the Freescale/Motorola HC11 · 1 Microcontrollers and the Freescale/Motorola...

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Microcontrollers and the Freescale/Motorola HC11

Summer 2008

CMPE12 – Summer 2008 – Slides by ADB 2

What is a microcontroller?A computer on a chip used to control

electronic devicesA microprocessor

Usually not cutting edge (4-bit to 32-bit)Dependable (all major bugs well known)Predictable (critical for real-time processing)On-chip peripherals and memory

Parallel and serial digital I/OAnalog I/OCounters and timersInternal ROM, RAM and/or EPROM

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What are microcontrollers used in?Microcontrollers are used in

WatchesMicrowavesStereo ReceiversATMsPDAs, MP3 playersAutomobiles (between 9 and 50)

Some products that you might know:NASA’s Sojourner Rover – 8-bit Intel 80C85Palm Vx handheld – 32-bit Motorola Dragonball EZSonicare toothbrush – 8-bit Zilog Z8The Vendo V-MAX 720 Soda Machine – Motorola HC11Miele dishwasher – 8-bit Motorola 68HC05Hunter 44550 Programmable Thermostat – (4-bit cpu)


Microprocessor unit salesMicroprocessor unit sales are 100 times higher than microcontroller sales

Microprocessor: 220 millionMicrocontroller: 20 billion

Microcontrollers are much, much cheaper

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Microcontrollers (1/4)AMCC

Until May 2004, these µCs were developed and marketed by IBM, whose 4xx family was sold to Applied Micro Circuits Corporation.403 PowerPC CPU

PPC 403GCX405 PowerPC CPU

PPC 405EPPPC 405GP/CR PPC 405GPrPPC NPe405H/L

440 PowerPC Book-E CPUPPC 440GPPPC 440GXPPC 440EP/EPx/GRxPPC 440SP/SPe

AlteraNios II 32-bit configurable soft processor Nios 16-bit configurable soft processor

AtmelAT89 series (Intel 8051 architecture)AT90, ATtiny, ATMega series (AVR architecture) (Atmel Norway design) AT91SAM (ARM architecture)AVR32 (32-bit AVR architecture)

Charmed LabsCypress MicroSystemsDallas Semiconductor


Microcontrollers (2/4)Freescale Semiconductor

Until 2004, these µCs were developed and marketed by Motorola, whose semiconductor division was spun-off to establish Freescale.8-bit

68HC05 (CPU05) 68HC08 (CPU08) 68HC11 (CPU11)

16-bit68HC12 (CPU12) 68HC16 (CPU16) Freescale DSP56800 (DSPcontroller)

32-bitFreescale 683XXMPC500MPC 860 (PowerQUICC) MPC 8240/8250 (PowerQUICC II) MPC 8540/8555/8560 (PowerQUICC III)

FujitsuHoltekInfineon

8-bitXC800 familyC500/C800 family

16-bitXC166 family

32-bit familyTRICORE family

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Microcontrollers (3/4)Intel

8-bitMCS-48 (8048 family – also incl. 8035, 8038, 8039, 8040, 8X42, 8X49, 8050; X=0 or 7) MCS-51 (8051 family – also incl. 8X31, 8X32, 8X52; X=0, 3, or 7) 8xC251

16-bitMCS-96 (8096 family – also incl. 8061) Intel MCS 296

Lattice SemiconductorMico8 softcore 8 bit microcontroller

Microchip Technology8 and 16-bit microcontrollers with 12 to 24-bit instructions ability to include DSP function 12-bit instruction PIC14-bit instruction PIC

PIC16F8416-bit instruction PIC

National SemiconductorCOP8CR16

NECPhilips SemiconductorsRabbit Semiconductor


Microcontrollers (4/4)Renesas Technology

(Renesas is a joint venture of Hitachi and Mitsubishi Electric.)SilabsSilicon MotionSTMicroelectronicsTexas InstrumentsToshibaWestern Design CenterUbicomXemicsXilinxZiLOG

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Languages for microcontrollers‘99-’00‘98-’99Language

~ 3 %

~ 1 %

~ 5%

~ 69%

~ 21%

~ 2%Other

~ 2%Java

~ 6%C++

~ 80%C

~ 10%Assembly

Source: TRON Association Survey 1998/99 & 1999/2000


Motorola / Freescale MC68HC11A8M6801 CPU coreMemory:

8KB ROM 512B EEPROM256B RAM

Counter/Timer system8-channel, 8-bit A/D converter

Analog to digital converter(external D/A in our kit)

Parallel I/O portTwo serial I/O ports:

Asynchronous, SCISynchronous, SPI

Expansion bus for external memory

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What are RAM and ROM?RAM: Random-access memory

Write to any location with the same effort(Same amount of time)

ROM: (Random-access) read-only memoryPROM: Programmable ROMEPROM: Erasable PROMEEPROM: Electrically-erasable PROMFlash EEPROM: Faster EEPROM


High-level HC11 architecture

Timer and counter M8601 CPU core

Serial I/O A/D converter

MEMORYInterrupt logic

Port A Port B Port C Port D Port E

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Our HC11 microkit

AC/DC Power adapterSerial cable

to PC

LCD

LEDs

Switches

HC11 µC

LCD display brightness control


Our HC11 microkit boardSerial (RS232C)

connector

EEPROM LEDs

Switches

HC11 µC

LCD display brightness control

External RAM

Interrupt

HW Reset

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HC11 programmer-accessible hardwareButtons

ResetInterrupt (IRQ)

Switches8 switches, MSb on far left and LSb on far rightAccessed by reading from SWITCHES

LEDs8 LEDs, MSb on far left and LSb on far rightAccessed by writing to LEDSActive low (writing a 0 turns a light on)

LCDTwo lines, 16 characters per lineWe provide some routines output to LCD


The HC11 instruction set architectureMixed 8-bit/16-bit architecture CISC, with more than 100 opcodesOne instruction can use several addressing modes, depending on how you use itAccumulator architecture

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An aside: accumulator architectureOne operand comes from memoryThe other comes from the accumulator


The HC11 accumulators and registersTwo 8-bit accumulators, or you can use them together as one 16-bit accumulator

Two 8-bit accumulators, A or BOne 16-bit accumulator [A:B], called D

Two index registersTwo 16-bit index registers, X and Y, used for addressing memory or for counting

Special registers16-bit dedicated stack pointer, SP16-bit program counter, PC8-bit condition codes register, CCR

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The HC11 registers


Accumulators: A, B, and DGeneral-purpose 8-bit accumulators

Source/destination of most operationsAlmost always interchangeable

E.g.,ABA, add B to A

A (A + B)B is unchangedNote that there is no AAB instruction

SBA, subtract B from AA (A – B)Note that there is no SAB instruction

7 A 0 7 B 0

15 D 0

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Accumulators: A, B, and DSome instructions use [A:B] as a single 16-bit register DE.g.

ADDD #2LDD #1MUL

7 A 0 7 B 0

15 D 0


Index registers X and Y

16-bit index registers X and Y:Used for indexed addressing modeSwap with register D to perform complex address operations

Address space: 64KBLC-3: 64K words, which is 128 KB

15 X 0

15 Y 0

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HC11 User StackThe HC11 has a stack set up at start-upMemory is byte-addressable

PSHA // push accumulator A onto stack// SP = SP – 1 since a byte size

PSHY // push index register Y onto stack// SP = SP – 2 since a word size

PULA // Pop off a byte from the stack into A// SP = SP + 1

PULY // Pop off a word from the stack into Y// SP = SP + 2


A

An aside: the RPN calculatorRPN is Reverse Polish NotationHP calculatorsE.g., A = CD+E

Push CPush DMultPush EAddPop A

CCDDE

TOPCD+E

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Stack pointer: SP16-bit stack pointer, SP

Automatically incremented or decremented on pushes and popsCan be used for data and return addressesReturn address for subroutines is automatically pushed with jsr and popped with rts

15 SP 0


Program counter: PC16-bit program counter, PC

15 PC 0

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Condition code register: CCRFive status indicators

H, half carry (used only for BCD operations)N, negativeZ, zeroV, overflow (two’s complement)C, carry/borrow

many instructions set them all, but not all instructions

Two interrupt masking bitsI, disable all maskable interrupts (1 = disable)X, disable external interrupts (1 = disable)

A STOP-disable bit disables the STOPinstruction

S X H I N Z V C


Programming on the HC11 microkitDesign environment:

Edit the source file Assemble on UNIX machine

> hc11build file.asm

Will produce an object (executable) file called file.s19Download program to the PC with terminal program TeraTermUpload to the microkit using serial cable

To use kits at homeGet one at BELSHave a connection to ITS machinesGet TeraTerm, which is free

Or any program which is capable of serial communication

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Programming on the HC11 microkitAs part of your program, always have

#include <v2_18g3.asm>

What the include file doesSets up memory, including the stack pointerJumps to the “main” labelIncludes a basic library of I/O routines


Structure of a source program/* header comments */


.sect .data// your variables here

.sect .text// your code heremain: // must have a main: function

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Example program – echo.asm#include <v2_18g3.asm>

.sect .datasignon: .asciz "CMPE12C Welcome!"prompt: .asciz ">"

.sect .text

main: ldx #signonjsr OUTSTRING // write a null-terminated

// string to serial portecho_loop:

ldx #prompt // address of promptjsr OUTSTRING // write out to serial portjsr GETCHAR // getchar returns in ACCAjsr OUTCHAR // write ACCA to screenjsr OUTCRLF // write '\n' to serial portjmp echo_loop


Example program – factorialThe factorial function

x! = x · (x-1) · (x-2) · … · 3 · 2 · 1Two ways to do it

RecursivelyNon-recursively

Draw a flow chartWrite an algorithm

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Example program – factorial.asm (1/2)12345678910111213141516171819


.sect .data

welcome: .asciz " Factorial !"prompt: .asciz "Fact is "blanks: .asciz " "input: .byte 0

.sect .text

main: ldx #welcomeldaa #1 // line 1jsr LCDSTRING // write to LCD, expects in Xldx #blanksinca // line 2jsr LCDSTRING // write to LCDldx #promptjsr LCDSTRING // write to LCD


Example program – factorial.asm (2/2)202122232425262728293031323334353637

ldab SWITCHES // B SWITCHESjsr fact_startjsr LCDINT // expects input in Dstab LEDS // LEDS B

always: jmp always

// factorial: assume input in B, output in Dfact_start:

stab input // input Btba // A B

fact: dec input // input (input – 1)ldaa input // A inputbeq fact_done // Z?mul // D (A·B)jmp fact

fact_done:rts

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Compiling the

program


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Downloading the program

Just drag & drop…


Running the program

Note the LEDs: is the number correct?

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Recommended exercises

Write and run the Fibonacci program.

Microcontrollers and the Freescale/Motorola HC11 · 1 Microcontrollers and the Freescale/Motorola...

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