Entry System. In this multipart group project you will develop a prototype of the deluxe version of the school's entry system (shown to the right) by interfacing a 12-Key keypad with an ATmega16 and your Optrex character LCD module.

Part 1. Interrupt On Any Key Pressed. TBD.

Part 2. Keypad Basics. Watch the Keypad 1 video. TBD.

Part 3. Single Pin Recognition and Display. TBD.

Part 4. 5-Pin Password Recognition, Display, and Confirmation (EEPROM). TBD.

External Interrupts: Photosensor. Watch the video entitled Photosensor. In this project you will interface a photomicrosensor with the ATmega16 to investigate the concept of an externally-generated interrupt. Photomicrosensors have many applications that include paper edge detection in printers and copy machines. Their operation involves the light of an LED emitter falling on an NPN Optotransistor. The device is considered ON as long as the beam is detected. If the beam is blocked, the device is OFF. The model you will be using is OMRON's EE-SX1081 (check out a sample of a wide variety of similar devices from OMRON or the EE-SX131).

LCD Experiment 3: Addressing. The standard Character LCD module has enough DDRAM for 80 characters but typically even fewer displayable positions. In 2-line mode (20 columns), this explains why the cursor disappeared (along with a number of characters) in the Entering Text video.

Task.

1. Read Experiment 3: Addressing in Part 1 of our LCD Guide starting at the bottom of page 10.
2. View the Addressing video.
3. With the support of your LCDdef.inc file, design and implement assembler code that focuses on the Set DDRAM instruction (0x80) to enable the direct addressing of DDRAM. You are free to display any character pattern you wish, but do so in a manner that confirms random (non-sequential) access to LCD module's display locations.

Include purpose, media (photo & video link) and code sections in your ER submission.

LCD Experiment 2: Entering Text. Now that you have a good sense of how commands and data are uploaded to the LCD module manually, you are ready to tackle the remaining Experiments outlined in Part 1 of our LCD Guide as programming projects.

Task. The Entering Text video to the right displays the output requested by Experiment 2 on pp. 8-10 of the LCD Guide. Create a project called EnteringText and develop fully documented assembler code to display the last 32 characters of the character table defined on page 9. Detailed interfacing and programming instructions can be found on pp. 30-46 in the DOT MATRIX CHARACTER LCD MODULE USER’S MANUAL. Note: It is not sufficient to simply have this project display the required output, rather, your well-structured code will contain the following,

1. LCDdef.inc. Just as the include file m16def.inc holds equates specific to the ATmega16 μC, you are asked to create a similar file to hold equates for our specific LCD module. Download the include file, LCDdef.inc to the root folder of your AVR projects, and add equates for as many instructions as are outlined in Table 3.1 List of Instructions on pp. 39-40 of the DOT MATRIX CHARACTER LCD MODULE USER’S MANUAL. For this and all future projects that use this LCD device, your code can include the assembler directive,

   	.INCLUDE "path\LCDdef.inc"

2. Program the data lines on PORTD and the control lines (RS, R/W, E) on PORTB.
3. Organizing your code into well-thought out subroutines will allow you to create future programming projects quickly and reliably. For example, develop subroutines to initialize the LCD unit, write a command, and write a data byte.
4. Program in the required delays as found within the 8-bit Initialization Flowchart on page 32 and the Execution Time column of Table 3.1 List of Instructions on page 39.

LCD Experiment 1: Basic Commands. The purpose of this assignment is to gain familiarity with the basic interfacing principles of a modern character-based LCD panel. You are asked to undertake the following steps.

1. Using the components you have been provided with, prototype the development circuit as profiled on page 5 of this primer complete with the debouncing circuit based on an SR NAND FlipFlop. Keep in mind that the driver/control circuitry is handled by an onboard chip. The industry standard for some time has been the Hitachi HD44780, but the new batch of Optrex C-51505 panels you are using are based on Novatek's NT3881D driver/controller architecture. This change requires one change in the wiring of the prototype that you are asked to uncover (Hint: examine the Timing Waveforms)
2. Next, undertake Experiment 1: Basic Commands and Experiment 2: Entering Text on pp. 6-10 and call me over for a video when you're ready.
3. Prepare an comprehensive ER writeup of your investigations complete with reasonably detailed tables, schematics, and explanations.

LED Cube 2. In version 2 of your LEDCube project, you are asked to incorporate a Timer0 Interrupt strategy to assist in achieving a 'Persistence of View' (or PoV) in a new pattern of your own creative design.

Your pattern should include distinct time intervals in which pairs or triples of LEDs within different levels and columns appear to be on simultaneously as part of a pattern of esthetic appeal.

Note 1: You will be asked to construct a standalone desktop model, so give your pattern some thought.
Note 2: Could you figure out a way to offer more than one pattern to users of your desktop model?

LED Cube 1. RBK suggested the LED Cube as an appropriate starting point for this year's course. I agree as it gets us into designing, building and simple testing right away. Review this PDF outline for an idea of where we're headed. Search the web under LED Cubes and study the various approaches that others have employed.

1. Using the supplied material (graph paper, plywood, drill and bits), create the jig folder holding the LEDs for soldering.
2. Solder up each level, testing as you go.

1. Solder the three levels together
2. Test the assembly and make any necessary corrections.

1. Final Manual Testing
2. Take photos and videos
3. Assembly language review

Friday September 25-Friday October 9

Over this period you will develop firmware that will light each of the 27 LEDs in a sequence of your own design. Delays between LED lightings should be a multiple of 0.5 seconds. For your ER writeup entitled LED Cube 1: Delay Loop, please include the following sections,

• Reference (include a link to the instructable)
• Purpose (your words)
• Procedure (your words)
• Code (include a fully formatted and commented listing in Courier 9-10 point
• Media (include a photo and link to video taken on Friday)