Learn about the fundamental processes underlying computing on your RasPi by using this adaptation of the classic LMC educational instruction set simulator. LMC – The Little Man Computer on the Raspberry Pi from Gordon Henderson:
I have added some extensions to LMC to modernise it from its 1965 roots. The first is the JSR and RET instructions. JSR is Jump to Subroutine and RET is return. In keeping with the simplicity of the system, there is only one register to store the program counter for the RET address. The other additions are for the Raspberry Pi’s GPIO. You can read a pin or set a pin to high or low. See the examples for details.
The RTB/Raspberry Pi implementation features three running modes – one is slow and runs at 10 instructions per second. This allows you to visually see the memory and accumulator changing as well as the program flow, the second is fast mode – the output register is updated, but that’s all, and finally you can single-step a program.
…The LMC is controlled by simple key-presses. On the main screen, you can move the active location (memory address highlighted in Yellow) using the arrow keys. To manually enter data or an instruction just type the numbers – the memory locations will only take the last 3 digits typed. Entering 1234 will result in 234 being placed into the memory location. Use the minus key (-) to negate the value. Pressing the Enter key moves to the next memory location….
Each Friday is PiDay here at Adafruit! Be sure to check out our posts, tutorials and new Raspberry Pi related products. Adafruit has the largest and best selection of Raspberry Pi accessories and all the code & tutorials to get you up and running in no time!
Have an amazing project to share? Join the SHOW-AND-TELL every Wednesday night at 7:30pm ET on Google+ Hangouts.
Join us every Wednesday night at 8pm ET for Ask an Engineer!
Learn resistor values with Mho’s Resistance or get the best electronics calculator for engineers “Circuit Playground” – Adafruit’s Apps!
Maker Business — Lessons Learned Scaling Airbnb 100X
Wearables — ABS ABC
Electronics — When do I use X10?
Biohacking — VICE Reviews The Internet’s Top Five Nootropics
No comments yet.
Sorry, the comment form is closed at this time.