Z80-Ruby

Ruby binding for the Z80 library.

Installation

First, make sure that you have the Z80 library installed on your system.

Then add the z80 gem to the Gemfile of your project and run bundle:

gem 'z80'

Or install the gem directly:

gem install z80

Troubleshooting

"I installed the Z80 library through Homebrew, but `bundle` does not find it."

Configure the environment variables C_INCLUDE_PATH and LIBRARY_PATH by adding the installation prefix of the library:

export C_INCLUDE_PATH="$C_INCLUDE_PATH:$(brew --prefix)/include"
export LIBRARY_PATH="$LIBRARY_PATH:$(brew --prefix)/lib"

"I installed the Z80 library through Homebrew, but `gem` does not find it."

Tell gem the installation prefix of the library:

gem install z80 -- --with-Z80-dir=$(brew --prefix)

Examples

Z80 Instruction Set Exerciser

This small script demonstrates how to run the CP/M versions of zexall and zexdoc with a few lines of code:

require 'z80'

memory = quit = nil
cpu = Z80.new

cpu.fetch_opcode = cpu.fetch = cpu.read do |context, address|
    memory[address]
end

cpu.write do |context, address, value|
    memory[address] = value
end

cpu.hook do |context, address|
    case address
    when 0 # END
        cpu.terminate
        quit = true
        0 # NOP
    when 5 # PRINT
        i = cpu.de
        while (c = memory[i]) != 0x24
            putc(c == 0xA ? "\n" : c) if c != 0xD
            i = (i + 1) & 0xFFFF
        end
        0xC9 # RET
    else
        0 # NOP
    end
end

$stdout.sync = true if $stdout.tty?

ARGV.each do |file_path|
    program = file_path == '-' ? $stdin.read : File.read(file_path)
    puts "#{file_path}:"
    quit = false
    memory = Array.new(65536, 0)
    memory[0x0100, program.size] = program.bytes
    memory[0] = memory[5] = Z80::HOOK
    cpu.power true
    cpu.pc = 0x0100
    cpu.run(Z80::MAXIMUM_CYCLES) until quit
    puts
    break if file_path == '-'
end

^{run-yaze-zex.rb}

Want to try it? Use this:

curl ftp://ftp.ping.de/pub/misc/emulators/yaze-1.14.tar.gz | tar -xOzf- yaze-1.14/test/zexall.com | ruby -e'eval `curl https://zxe.io/software/Z80-Ruby/scripts/run-yaze-zex.rb`' -

Zilog Z80 CPU Test Suite

This runs any tape from Patrik Rak's Zilog Z80 CPU Test Suite (except z80ccfscr.tap):

require 'z80'

module Opcode
    RET  = 0xC9
    NOP  = 0x00
    CALL = 0xCD
end

quit = cursor_x = tab = memory = nil
cpu = Z80.new

cpu.fetch_opcode = cpu.fetch = cpu.read do |context, address|
    memory[address]
end

cpu.write do |context, address, value|
    memory[address] = value if address > 0x3FFF
end

cpu.in do |context, port|
    port.odd? ? 255 : 191
end

cpu.hook do |context, address|
    case address
    when 0x0010 # PRINT
        if tab == 0
            case (c = cpu.a)
            when 0x0D # CR
                putc "\n"
                cursor_x = 0
            when 0x17 # TAB
                tab = 2
            when 0x7F # ©
                printf "©"
                cursor_x += 1
            else
                if c >= 32 && c < 127
                    putc c
                    cursor_x += 1
                end
            end
        elsif (tab -= 1) != 0
            c = 0x1F & cpu.a
            x = 0x1F & cursor_x
            if c < x
                putc "\n"
                cursor_x = 0
            else
                cursor_x += (c -= x)
            end
            print ' ' * c
        end
        Opcode::RET
    when 0x7003 # Exit
        cpu.terminate
        quit = true
        Opcode::NOP
    else
        Opcode::NOP
    end
end

$stdout.sync = true if $stdout.tty?

ARGV.each do |file_path|
    program = file_path == '-' ? $stdin.read : File.read(file_path)
    puts "#{file_path}:"
    quit     = false
    cursor_x = tab = 0
    memory   = Array.new(65536, 0)
    memory[0x8000, program.size - 91] = program.bytes[91..-1]
    memory[0x0010] = Z80::HOOK    # THE 'PRINT A CHARACTER' RESTART
    memory[0x0D6B] = Opcode::RET  # THE 'CLS' COMMAND ROUTINE
    memory[0x1601] = Opcode::RET  # THE 'CHAN_OPEN' SUBROUTINE
    memory[0x7000] = Opcode::CALL # -.
    memory[0x7001] = 0x00         #  |- call 8000h
    memory[0x7002] = 0x80         # -'
    memory[0x7003] = Z80::HOOK
    cpu.power true
    cpu.im = 1
    cpu.i  = 0x3F
    cpu.pc = 0x7000
    cpu.run(Z80::MAXIMUM_CYCLES) until quit
    break if file_path == '-'
end

^{run-raxoft-z80test.rb}

Want to try it? Use this:

curl http://zxds.raxoft.cz/taps/misc/z80test-1.2a.zip | bsdtar -xOf- z80test-1.2a/z80full.tap | ruby -e'eval `curl https://zxe.io/software/Z80-Ruby/scripts/run-raxoft-z80test.rb`' -

License

Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.