====== Revised: Jan 14, 2007,  Chaoji Li<lichaoji@ict.ac.cn> ===========

There are some other MIX simulators in the world, but none of them
is in Perl. 

That's why I start to write this one. 

It supports almost all instructions, except support for typewriter,
paper tape, and float operations.

Card reader/punch and printer are supported.
Disk/tape are partial supported.

========================================================================
 I N S T A L L
========================================================================

Install "Build" module from CPAN.

perl Build.PL
perl Build
perl Build test
perl Build install

========================================================================
 Q U I C K   S T A R T
========================================================================

In the package directory, 

>perl mixasm.pl mixal/primes

Three files will be generated in the current directory.

   * primes.lst -- listing files
   * primes.mix -- memory dump file
   * primes.crd -- card deck file which can be loaded by mix simulator

>perl mixsim.pl --batch --cardreader=primes.crd

The outputs are:

== PAGE 1 OF 1 ==
FIRST FIVE HUNDRED PRIMES
     0002 0233 0547 0877 1229 1597 1993 2371 2749 3187
     ...
     0229 0541 0863 1223 1583 1987 2357 2741 3181 3571     

You can also enter the interactive mode. An example session is
shown below.

>perl mixsim.pl primes.crd


    M I X   S i m u l a t o r

Type 'h' for help messages.
MIX> g 3000
 rA: + 00 00 00 00 00 +0
 rX: + 00 33 30 30 30 +8775582     3000
rI1: + 00 00 +0000   rI2: - 00 30 -0030
rI3: + 46 56 +3000   rI4: + 00 00 +0000
rI5: + 00 00 +0000   rI6: + 00 00 +0000
 rJ: + 00 14 +0014   NO EQ  1325u
3000: IOC  0,0(18)
MIX> g 3029
 rA: + 30 30 30 30 30 +511305630  00000
 rX: + 30 30 32 32 39 +511313959  00229
rI1: + 00 00 +0000   rI2: + 55 51 +3571
rI3: + 00 19 +0019   rI4: + 31 51 +2035
rI5: + 00 00 +0000   rI6: + 00 00 +0000
 rJ: + 47 18 +3026   NO EQ  1183474u
3029: HLT  0,0(2)
MIX> prt
Page 1 of 1
FIRST FIVE HUNDRED PRIMES
     0002 0233 0547 0877 1229 1597 1993 2371 2749 3187
     ....
     0229 0541 0863 1223 1583 1987 2357 2741 3181 3571
MIX>


========================================================================
 C H A N G E   L O G
========================================================================
0.3: Feb 28, 2008

    - Fix unasm bug CMP? not handled
    - Fix MIX.pm: our deprecated, add document

0.2: Feb 27, 2008

    - Add unasm in mixsim.pl
    - Add print machine status
    - Remove the print_all_regs in MIX.pm

0.10: Feb 24, 2008

    - Add CON support for mixasm.pl, parse_w_value

0.09: Feb 17, 2008

    - Fix bug: mixasm.pl: no TRANS card if no end of line after "END
      START"

    - Add feature: show execution count and time for
      instrunctions in the 'd' command


0.08: Feb 07, 2008

    - Fix a timing bug in wait_until_device_ready (+=)

0.07: Feb 06, 2008

    - Add timing

0.06: Jan 14, 2007

    - Add disk and tape support
    - rewrite io device management

0.05: Dec 13, 2006

    - support full instructions
    - support only part of the io devices(card reader/punch, printer)

0.04: 
    - Apr. 2006: mixsim.pl: add a command line user interface
               : mixasm.pl: add generate code 

    - Nov. 2006: create test cases; fix some bugs

0.03: add mixasm.pl
0.02: add load operations, display registers and flags
0.01: basic reset, only halt instruction

.