AVR STUDIO

• The AVR Studio is Atmel's answer to PIC's MPLAB.
  
• AVR Studio is an IDE for writing and debugging AVR applications in Windows environments.
  
• It provides a project management tool, source code editor, simulator, assembler, front-end for compilers, debugger.
  
• The popular open-source GCC compiler is available for AVR Studio packaged as WINAVR.
  
• Download and install WINAVR first, then AVR Studio. GCC automatically included as a compiler plug-in.
  
• Optimised code, wide user base, forum support, free.
  
• Compiler and library supports all AVR microcontrollers: ATMEGA, ATTINY, AT90, ATXMEGA

AVR SIMULATOR

• AVR Simulator is a software simulator for the AVR devices. It simulates the CPU, including all instructions, interrupts and most of the on-chip I/O modules.
• The AVR Simulator operates within the AVR Studio application as a debug target.
• You can use normal debug commands such as Run, Break, Reset, Single step, set breakpoints and watch variables.
• The I/O, memory and register views are fully functional using the AVR Simulator.
• Debug by single stepping through C or assembler code.
• You can test your code before burning into chip.

HAPSIM

• HAPSIM stands for Helmi's AVR Periphery Simulator
• Provides software-simulated LCD, USART/UART and TWI, LEDs, Push-Buttons and Keypad for the AVR Simulator.
• With AVR Studio and HAPSIM in a laptop, you have a nice, portable workbench to experiment with various projects.
• Think of long bus trips, waiting at airports, ships, boring dates, etc.
  
  
  
  
• Supports one or more of the following components simultaneously:
  1. HD44780U compatible LCD with 40 x 2 or 20 x 4 characters.
  2. Pushbuttons connected to Input Port Pins.
  3. LEDs connected to Output Port Pins.
  4. Terminal connected to USART, UART or TWI(I2C) ports.
  5. 4x4 Matrix Keypad.
  6. Watch Cycle Counter and Simulation Speed
• Easy configuration of the components using XML files.
• Targets all microcontrollers supported by the AVR Simulator.
• AVR Studio Version 4.12.452 or higher strongly recommended.
• Code tested with HAPSIM simulator will run on chips (and vice versa).
• Build and run your code in the simulator. It will break at first line.
• Run HAPSIM.EXE then open an existing XML config file.
• Or create new control and add i/o components eg. button, leds.
• Each component has customisable settings eg. PORT, bits.
• Remember to specify your CPU type.
• Once all components are set up, save settings in XML file.
• Continue program simulation and test the virtual peripherals.
• Always build with -DFASTSIM to fake delay timers.

Demo

The supplied demo programs exercise the various HAPSIM components.

• LCDTest
  Simulates an LCD connected to an ATmega128 PORTA Pin 4-7
  
  
  
  Cursor - cycles thru _, _block, block, invisible cursor
  Mode 0: Left/Right overwrites chars
  Mode 1: Left/Right move cursor
  Mode 2: Left/Right shifts display
  Mode 3: Left/Right changes bitmap display
  Must reset program to return to Mode 0.
  
  
• USART2TWI
  Connects a terminal to USART0 and terminal to TWI (PORTD).
  Data received from USART0 is written to TWI.
  Data received from TWI sent to USART0.
  
  
  
  
• UART Terminal sends data to USART0 which echoes it back. Code also tested on an actual ATtiny2313 with no change.
  
  
• TestKeypad
  
  Simulates a 0-9 cursor keypad with selection sent to terminal.
  Must define D FASTSIM in Project -> Config Options -> Custom Options.
  
  
  
  
• Trinary Button
  
  
• utrans
  
  
• ToggleLED
  Pushbutton turns LED on/off but has startup bug. Code also tested on an actual ATtiny2313 with no problems.

Tips and Tricks

• Must specify correct F_CPU clock speed for baud rate to work properly.
• Single-stepping can give misleading results with uart i/o.
• Disable code optimisation for debugging. But larger code size, timer delays and watchdog affected.
• Switch debounce using delays do not simulate accurately unless you specify -D FASTSIM build option.
• Certain antivirus eg. Trend Micro will block HAPSIM dll hook.
• Always stop AVR simulation before closing HAPSIM.