Source Programming Hints:
- In Assemble, use the bottom left File
icon to open the source directory. There are 6 example source
- You can change and modify each of the example source files
as you wish. Remember to Save it you want to keep.
- You can add your own source programs. Clear the edit field
-- use File icon and select the + symbol top
- Assemble source using the Assemble button top right.
- After assemble, use the Save button, bottom left, to
save the assembled object code for future execution.
- In the source edit field, use the Tab key (iPad Pro
models only) to align fields. (Or double tap Space Bar
- The Assembler Manual is found via the Book icon on the
bottom right of edit field.
Running Program Hints:
- Like a real computer, you must first power it on to
use it. This will display an Overview of the Architecture.
- The IPL button will load the computer microcode.
These define the hardware instructions and are listed for
- The Load button will display the object directory.
If it is empty, you must first assemble a program and save
- The Loaded program will be displayed via a memory
and register dump.
- The Run button will start the clock and display the
microcode progress via display lights and LED
- The Step button will step through the instructions
and wait for you to continue -- displaying status on each
- The Halt button will stop the clock and the end of
the current instruction (it will complete instruction
- Once halted, the program may be continued via the
- Display and clock speed options can be
controlled via the Settings main screen menu.
- You can decide to show or hide the register & program
dumps after each microcode step and/or each instruction.
- To help visualize real computer start up, you can decide to
fill registers and memory with initial values that are:
You can set the frequency of the clock, in seconds. Slow the
clock to see more detail or speed it up to get results.
At certain clock speeds, the register and memory dumps
become unusable and are therefore turned off automatically.
The slider will equate the clock timing from
seconds to hertz so you can compare CPU speeds to other
- Random -- like you'd find with a real computer at
- Predicable contents -- zeros in registers and
memory address in memory each location
- The videos are provided to give the user an indepth
understanding of all aspects to the CPU8 model.
- While describing the details about each CPU, Ben Eater
provides an astonishing treasure trove of information.
If you run into problems, have suggestions or would like to
contribute to this project, please send an email to:
firstname.lastname@example.org and we will respond as soon as we can.
Enjoy and let us know if you write an interesting new program.