What will be tested.

A outline of what's in the test.

The test will be in our normal classroom on Thursday 9th June at 8:08am

There will be a picture of an Arduino like this below and you'll annotate it with text and arrows. You may be asked to identify a crystal, capacitor, resistor, LED or voltage regulator too.

There will be one of the two pages from the Atmel mega 328 family's data pdf. You'll be required to comment on some of the functions in the page below and most of the features in the very front page.







There will be questions about a schematic involving the Arduino red board like the one below.

The red board schematic is on another page and in Spark Fun's site.

Test Information

There will be a theory test on Thursday 9 June. It will be closed book and you must complete it in 1 hour and 45 minutes.  All the items in the test we have discussed in class or will be notified in a revision class prior to the test. 

There will be a question on the main parts of the Arduino. See the labelled diagram above. This is not exactly the same as our Arduino but, apart from the DIL processor, USB to serial IC and colour, is pretty close.

There will be a question on the page above called The Front Page of the Mega328. You will be expected to write a sentence explaining some of the features listed. 

There will be questions on the functions diagram of the Mega328. You will be given a copy of this diagram and be expected to write a short paragraph on up to three blocks.

There will be a question about the Arduino schematic diagram above or similar.

Also there's buggy program. A program will be given to you with errors in it. You will have to identify the errors. Mostly syntax violations.

A problem to do with sampling real world inputs will be given and you will be asked how you would respond to this using the Arduino.

You will be asked to write a simple assembly language program. You will be asked to write a program in Arduino C.

There may be other questions but only on items we have studied in class including serial buses, pin outs of the Arduino and the mega328p, voltage dividers, the stack and interrupts.

Please contact me about any problems. Good luck.

PeterB

Mega 328p features from front of Atmel's pdf.

from this site

Red board schematic

The above schematic is found in this site.

There are four sorts of memory on the Arduino

The UNO's schematic

A good introduction to reading a schematic

The i2c bus

Most popular of the serial buses. Uses one wire for clock and one wire for bidirectional data. Based on Phillips' iic network. Lots of chips use the i2c protocol.

Good short introduction here. Not Arduino based.

Using i2c to connect arduino to eeprom chip that holds 256k bits, here.

Interesting use of i2c OLED display.

SPI or i2c. Which one is ""better"?

The SPI bus

Fastest of the serial I/O on the Arduino.

A good tutorial on spi using a digital potentiometer chip here

A tutorial on the spi bus, more technical here

Two Arduino's connected via spi here. Code via link to github.

Using AVR Studio programs in an Arduino (Not required for 2016, but asm blink program is relevant)

Programs needed are just AVR Studio and avrdude. I used AVR Studio version 4.14 and the avrdude that came with the Arduino suite.

Step 1. Write your program in assembler in AVR Studio, build then save the hex file.
Step 2. Go into the command prompt and invoke avrdude with the right switches.

I started with the usual Arduino C blink program, just to make sure I got the COM port right and to see the hardware was all working. Then did steps above.

Below are some relevant screen shots.

Blink for AVR Studio 4 assembler


.include "m328pdef.inc"


;Based on http://www.robertoinzerillo.com/wordpress/?p=5
;-----------------------------------------;
; FIRST WE'LL DEFINE SOME REGISTER TO USE ;
;-----------------------------------------;
.DEF A = R16   ;GENERAL PURPOSE ACCUMULATOR
.DEF I = R21   ;INDEXES FOR LOOP CONTROL

.ORG $0000

;-----------------------------------------;
; FIRST WE SETUP A STACK AREA THEN SET    ;
; DIRECTION BIT ON PORT-B FOR OUTPUT/SPKR ;
;-----------------------------------------;
START:
  LDI A,LOW(RAMEND)   ;SETUP STACK POINTER
  OUT SPL,A           ;SO CALLS TO SUBROUTINES
  LDI A,HIGH(RAMEND)  ;SETUP STACK POINTER
  OUT SPH,A           ;SO CALLS TO SUBROUTINES

  LDI A,0b1111_1111   ;SET ALL PORTB FOR OUTPUT
  OUT DDRB,A          ;WRITE 1s TO DIRECTN REGS

;--------------;
; MAIN ROUTINE ;
;--------------;
LEDONOFF:
  SER A
  OUT  PORTB,A
   RCALL DELAYLONG
  CLR A
  OUT PORTB,A
   RCALL DELAYLONG
  RJMP LEDONOFF


DELAYLONG:
; =============================
; Delaying approximately 1 sec at 8Mhz.
; This code has been created with  “AVR Delay Loop Generator V1.2?.
          ldi  R17, $48
WGLOOP0:  ldi  R18, $BC
WGLOOP1:  ldi  R19, $C4
WGLOOP2:  dec  R19
          brne WGLOOP2
          dec  R18
          brne WGLOOP1
          dec  R17
          brne WGLOOP0
; =============================
RET

Setting up stack for subroutines

The code for the above program is:

.include "m328pdef.inc"
start: ;set up the stack
ldi r16, low(RAMEND)
out SPL, r16
ldi r16, high(RAMEND)
out SPH, r16

nop

call below
nop

finish: rjmp finish
below:
ldi r17,$99
ret

The relevant part of the def.inc file the shows what RAMEND is for this processor is:

; ***** CPU REGISTER DEFINITIONS *****************************************
.def XH = r27
.def XL = r26
.def YH = r29
.def YL = r28
.def ZH = r31
.def ZL = r30



; ***** DATA MEMORY DECLARATIONS *****************************************
.equ FLASHEND = 0x3fff ; Note: Word address
.equ IOEND = 0x00ff
.equ SRAM_START = 0x0100
.equ SRAM_SIZE = 2048
.equ RAMEND = 0x08ff
.equ XRAMEND = 0x0000
.equ E2END = 0x03ff
.equ EEPROMEND = 0x03ff
.equ EEADRBITS = 10
#pragma AVRPART MEMORY PROG_FLASH 32768
#pragma AVRPART MEMORY EEPROM 1024
#pragma AVRPART MEMORY INT_SRAM SIZE 2048
#pragma AVRPART MEMORY INT_SRAM START_ADDR 0x100



; ***** BOOTLOADER DECLARATIONS ******************************************
.equ NRWW_START_ADDR = 0x3800
.equ NRWW_STOP_ADDR = 0x3fff
.equ RWW_START_ADDR = 0x0
.equ RWW_STOP_ADDR = 0x37ff
.equ PAGESIZE = 64
.equ FIRSTBOOTSTART = 0x3f00

Assembler delays

Using delays in AVR studio

Write a variation on the above program to produce any delay required fro your project.

Using AVR Studio

You'll need to download AVR Studio 4.19 for further work on AVR assembly language.