INTRODUCTION
   Z80 disassembler in Emacs Lisp

HISTORY
   I needed to dig through some 1980s vintage Z80 programs to try and
   track down a problem.  I had the executables but no source.

   I only had access to a Windows NT box which had previously been
   used for Java development.  I initially planned to write a Z80
   disassembler in Java but on finding that the box also had Emacs
   installed I switched to Emacs Lisp.

   I started on 1997-11-17 and stopped on 1998-01-05 when I had enough
   of a working disassembler for my purposes.  Between those days I
   worked on it on 9 separate days and for a total of 25 hours and 56
   minutes i.e. on average almost 3 hours each of the 9 days.

BUILD
   To speed up disassembly it is best to byte-compile all the files :-

      $ make all

RUN
   Since it is written in Emacs Lisp it is meant to be used interactively.
   So, in an Emacs *scratch* buffer do :-

      (setq load-path (cons "." load-path))
      (load-library "z80-dis")

   to load the code and now to disassemble the first 10 instructions of "sort.bin"
   first load the file and create a disassembler on it :-

      (setq *d* (z80-dis-from-file "sort.bin"))

   Now you can disasemble any section of it tha you want, the
   following disassembles the first 10 instructions :-

      (z80-dis *d* 0 10)
      0000 0e00     LD	C, 0
      0002 214000   LD	HL, 64
      0005 46       LD	B, (HL)
      0006 05       DEC	B
      0007 23       INC	HL
      0008 7e       LD	A, (HL)
      0009 23       INC	HL
      000a be       CP	(HL)
      000b 3007     JR	NC, 0014
      000d 56       LD	D, (HL)

BIBLIOGRAPHY
   Z80 Assembly Language Programming
   Lance A. Leventhal
   Osborne/McGraw-Hill 1979

     Table 3-4 on pages 3-23 to 3-39 contains a summary of the Z80
     instructions ordered by type i.e. I/O, block transfer, ... etc.
     The table also listes the order code, number of bytes, clock
     cycles and affect on flags.

     Table 3-5 on pages 3-40 to 3-42 has a table listing the
     instructions in numeric order.

     Pages 3-43 to 3-163 contain a detailed description of each
     instruction ordered alphabetically.

     Pages 9-10 through 9-14 contains an 8-bit bubble sort which
     includes the hex machine code as well as the assembly code.

   Programming the Z80
   Rodnay Zaks
   Sybex 1980

AUTHOR
   Ninetes Retro <nineties-retro@mail.com>

   1b4cb78552a8a5eac4e6cd7c21cc54cec15e03c8c551167fb3fd4b26081063c9