TECH 4234
Microprocessor Interface Technology
Fall 2023

Instructor Info

Daniel Kohn
Office ET218
Phone: 678-4515
Office Hours

Course Info

Course Policies
GradeWatch Access

Assignment Submission

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Required Text

The AVR Microcontroller and Embedded Systems Using Assembly and C: Using Arduino Uno and Atmel Studio by Sarmad Naimi and Muhammad Ali Mazidi 2nd Ed

Author's Website

Previous Courses

TECH 3233 - Microprocessors
TECH 3812 - Digital Communications

Required Software

MicroChip Studio (Formerly Atmel Studio 7) - note: "Download Microchip Stuido button does not seem to work, scroll down to "Downloads and Documents"
Arduino IDE (Install Legacy IDE 1.8.x for avrdude utility)

Course Outline:

Aug 23Welcome

Sync Serial
Review Interrupts for Next Class Chp 10.3 and Lab 6

Review Synchronous Serial for next class

Sync Serial Fundamentals

PS2 Synchronous Serial Keyboard
Review Chp 10
Lab #0 - Due tonight. Install MicroChip Studio. Open a project, replace main.c with THIS CODE and upload it to the board. Demo to instructor. This verifies the new install of the software, the drivers can be installed on the new image, and you remember how to set up and upload code to the Arduino.

Lab #1 - Write a program to read a magnetic card (credit card). The data sheet for the card reader is available HERE. Info on the data format is available HERE. Most credit cards use ANSI/ISO BCD Data Format. CLICK HERE for a sample waveform.

For Procedure step 5, those in TECH 6234 must translate the card data into the card number, those in 4234 will get a bonus for doing it in their program, but can can also prove the data bits read from the card are correct by interpreting them by hand and turing the hand interpretation with the assignment.
Aug 28Work on Lab #1   
Aug 30|   
Sep 4|   
Sep 6|  Lab #1 Conclusion 
Sep 12UART/USARTBasics of UART Communication


Asynchronous Serial (Hackaday)
Uart Lecture
Chp 11
Lab #2
Sep 14|   
Sep 19|   
Sep 21|   
Sep 26|   
Sep 28SPIWhat could go wrong: SPI (Hackaday)


SPI Explained (Note code for different uProc)
Lecture NotesLab #3
Oct 3|  
Oct 5No Class/Lab (Family Emergency)   
Oct 10|  
Oct 12|  
Oct 17No Class (Fall Break)   
Oct 19|  
Oct 24|  
Oct 26
I2CChp 18

What Could Go Wrong? I2C Edition (Hackaday)
Lecture NotesLab #4a - get program 18-13 working for RTC. We will replace the uart routines in the sample code and use printf instead.

Link is broken in doc for Escape Sequences, use THIS LINK instead (just remember that <ESC> is \E in printf statements).
Oct 31|  Lab #4b - due end of lab Nov 7.
Nov 2|   
Nov 7|   
Nov 9WiFi Using ESP8266  AT Commands
AT Commands
Lab #5

We will use Software Serial Template add to start this project. Download, unzip and open to start YOUR code. Due Nov 16 at end of lab.

For the GET /save_get.php... there is a SPACE between "GET" and "/save"! It will error if this space is missing!
Nov 14|   
Nov 16|   
Nov 21No Class - Instructor Ill   
Nov 23No Class (Thanksgiving Break)  
Nov 28End of Semester Project Discussion ESP8266 AP Mode

AP with DHCP
Lab #6
Nov 30|  
Dec 5|  
Dec 7Study Day (Project, Demo and Q&A due)  

Reference Links:

New MicroChip Website
ATmega328P Datasheet (new link)
ATmega328P / Arduino pinout
C Quick Reference

Tutorialspoint C Programming
What's all this _BV() stuff

Various AVR Articles

VT100 Escape Codes

C Style Guides

Rigol Digital Oscilloscope - 2000 Series
• (note: to use USB Stick, it MUST be formatted as FAT32)

Arduino Ethernet Shield 2
WIZ5500 IC
Real Time Clock (BOB 12708)
16x2 SerLCD
ADXL345 Tripple Axis Accelerometer
Transceiver (nRF24L01+)
Wifi Module (ESP8266)
Bi-Directional Logic Level Converter

Info needed for Labs

Determine Com Port

With Arduino plugged in to computer's USB port
Win 10 - Search for "Powershell" and open
Type - "Get-WMIObject Win32_SerialPort" (no quotes)
check results for Arduino Uno (Com __ )

Atmel Studio

Setup Strings:

C:\Program Files (x86)\Arduino\hardware\tools\avr\bin\avrdude.exe

-C "C:\Program Files (x86)\Arduino\hardware\tools\avr\etc\avrdude.conf" -p atmega328p -c arduino -P COM7 -b 115200 -U flash:w:"$(ProjectDir)Debug\$(TargetName).hex":i"

Atmel Studio add ins:

Microchip Gallery

Go to above link then search for "Microchip Gallery". Click on "Download" on left side of screen and run the downloaded file (if Atmel Studio was opened when you did this, close and reopen Atmel Studio). This should now allow Atmel Studio access to plugins (TOOLS | Extensions and Updates). It is suggested in go ahead and install "Terminal for Atmel Studio"

To get printf to work with floating point values:

Project | nameofproject Properties | Toolchain : AVR/GNU Linker | General | Check "Use vprintf library(-Wl,-u,vfprintf)"
Project | nameofproject Properties | Toolchain : AVR/GNU Linker | Miscellaneous | Other Linker Flags put into textbox | "-lprintf_flt" (leave off quotes).

For ATmega 2560

ATmega2560 Datasheet

2nd setup string:

-C "C:\Program Files (x86)\Arduino\hardware\tools\avr\etc\avrdude.conf" -p atmega2560 -c wiring -P COM3 -b 115200 -U flash:w:"$(ProjectDir)Debug\$(TargetName).hex":i"

if you get an error that says:

avrdude.exe: Device signature = 0x1e9801 (probably m2560)
avrdude.exe: NOTE: "flash" memory has been specified, an erase cycle will be performed
             To disable this feature, specify the -D option.
avrdude.exe: erasing chip
avrdude.exe: stk500v2_command(): command failed

you need to add a -D to the 2nd setup string like this:

-C "C:\Program Files (x86)\Arduino\hardware\tools\avr\etc\avrdude.conf" -p atmega2560 -c wiring -P COM3 -b 115200 -U flash:w:"$(ProjectDir)Debug\$(TargetName).hex":i"

Using Multiple Usarts:

When you start the project, pick the number of USARTS you need. In Each USART, change the mode to Async IRQ Mode and make sure you enable Printf support. You can adjust the RX and TX Buffer size to meet your needs.

at the start of you code (above atmel_start_init();) you will need to add the following line:


where x is the USART number (you will need to add this line for EACH USART you wish to use 0-3).

to get characters:


to print stuff, put it in an array (buffer in the example below) with sprintf then send to usart with fprintf:

sprintf(buffer,"Hello World\n\r");