Pyntel4004 1.2

A Python software implementation of the Intel 4004 processor.

Pyntel4004

A Python software implementation of the Intel 4004 processor and the MCS-4 computer.

General Information

• Two pass assembler using the original mnemonics, directives and comments syntax
• Disassembler
• Monitor facility to step through code and examine registers, memory etc
• Cross-assembler for Retroshield 4004 Arduino

Requirements

• Python >= 3.8.2

Installation Instructions

PyPI

Pyntel4004 can be installed from PyPI by using the command:

    $ pip install Pyntel4004

Source Code

Pyntel4004’s git repo is available on GitHub, which can be browsed here and cloned using:

    $ git clone https://github.com/alshapton/pyntel4004 pyntel4004

Verify the installation by running unit tests:

    $ cd pyntel4004/test
    $ pytest

Questions, Answers and Issues

Please use the github discussion board for questions, to ensure the right people see them in a timely manner.

Github Pyntel4004 Discussion Board

and the github issue tracker to raise any issues.

Github Pyntel4004 Issues Board

Usage Instructions

To use this software implementation of the Intel 4004 from the command line, you should install the Pyntel4004-cli using pip install pyntel4004-cli

The user instructions can be found here

Design goals

• As much of the internals as possible should be carried out using binary arithmetic and operations.
• No 3rd party libraries to be used (i.e. pure Python).
• Build a fully-working i4004 opcode emulator.
• Build a fully-working assembler which generates correct op-codes.
• Construct a fully-working software-based i4004 chip which can use the generated object code from the assembler.
• Enable code assembled with Pyntel4004 to be run on a real i4004 chipset
• Enable code assembled with Pyntel4004 to be run on a retroShield4004 for Arduino

Status

22-MAY-2022 First release of configuration file support 20-MAR-2022: Command Line functionality is now deprecated 02-MAR-2022: Finalised split - Pyntel4004 is now the core library 21-FEB-2022: Started to split into two - (chip, assembler, dissassembler) and CLI 04-FEB-2022: Cross-assemble to retroShield4004 for Arduino, completing documentation 23-SEP-2021: Publishing releases to PyPi
10-SEP-2021: Documentation building and hosted with READTHEDOCS
12-JUN-2021: Auto-build with GITHUB Actions implemented
18-MAY-2021: Implementing full test suite
21-APR-2021: Instruction Set functionally complete Entering Testing Phase

Example

Assembler Directives and other additions

Assembler directives are not part of the program itself, but can control things like starting address, and various environmental settings.

Directive	Example	Meaning
end	end	Indicating end of program, but not necessarily end of code
org	org 100	Assemble and place object code commencing at address 100
pin	pin 1	Value of i4004's Pin 10 (test pin)
/	/ Author: ALS	A comment
label,	loop,	A label can be referred to in various control transfer statements. It MUST end in a comma (,)

Monitor Commands

Command	Example	Meaning
"Enter"	"Enter"	Execute the current instruction and move to the next
acc	acc	Show the current contents of the Accumulator
b n	b 71	Create a breakpoint at address n
carry	carry	Show the current contents of the Carry Bit
crb	crb	Show the currently selected RAM Bank
off	off	Continue to execute the program with no trace
pc	pc	Show the Program Counter
pin10	pin10	Show the status of PIN10 on the i4004 chip (test pin)
q	q	Quit the monitor without executing any further commands
ram	ram	Show the complete contents of RAM
reg n	reg 7	Show content of a specified register
regs	regs	Show all 16 registers
rom	rom	Show the complete contents of ROM
stack	stack	Show the stack and the location of the stack pointer

Licence

This package is Treeware. If you use it in production, then we ask that you buy the world a tree to thank us for our work. By contributing to the Treeware forest you’ll be creating employment for local families and restoring wildlife habitats.

Credits

• Intel 4004 Design Team
• Logo: LouBeLou Print Shop

.. _Python: https://www.python.org