Forth-eV Wiki

  Software Review

               * LABORATORY MICROSYSTEMS Z-80 FORTH 3.0 for CP/M *

                              by Richard C. Secrist


            Editor's Note:  Since the publication of this issue  over
            a   year  ago,  LMI  has  updated  their  product  making
            extensive changes to the documentation which now puts  it
            into  the  superlative class...  as of 1/8/85 the current
            release was Version 3.10.


  < OVERVIEW >

  Laboratory Microsystems Inc.  (LMI) Z-80 FORTH version 3.0 is an  83-Standard
  Forth  development system optimized for the Z-80 uP that runs as a task under
  CP/M.  The disk and console interface make use of the host  operating  system
  and provide high level compatability with other LMI Forth implementations for
  various microprocessors.  Z-80 Forth uses standard CP/M  random  access  data
  files  for  screen storage, so its programs and data coexist on the disk with
  other applications and may be manipulated with standard system utilities.

  < UTILITIES >

  Z-80 Forth includes full screen and line editors, an  assembler,  decompiler,
  and extensive file I/O facilities.

  The full-screen editor uses Wordstar-like command sequences and is  adaptable
  to   sundry   video  terminals  through  the  video  attributes  installation
  procedure.  If you are either new to Forth or lazy the manual offers  you  an
  easy  way  out  of  configuring  Z-80 Forth to your terminal by hand.  Simply
  photocopy the cursor and attribute control section out of your terminal  book
  and  send  it  to them with your distribution diskette.  Then LMI will return
  your disk via express mail with your terminal listed as one of the choices on
  the installation menu.  This saves you the grief of having to do it yourself,
  and helps LMI out because their Forth now supports the XYZZY  type  terminal.
  This  also  configures  your  copy  of Forth to take advantage of the various
  video-support words made available in Z-80 Forth (e.g.   CLEARSCREEN,  BLINK,
  UNDERLINE).

  The assembler uses standard Zilog mnemonics in the traditional Forth  postfix
  style.   Other assorted utilities include a decompiler, notable benchmarks, a
  non-destructive stack print routine, and even memory dumps in  byte  or  word
  format.   Software  floating point and AMD 9511 chip support are available at
  extra cost.

  < EXTENSIVE FILE I/O SUPPORT >

  One of the most outstanding features of the LMI product is superior file  I/O
  support.  From within FORTH the programmer is given access to a very powerful
  complement of disk file and record  interface  routines.   The  routines  are
  sufficiently powerful to allow you to get yourself into a lot of trouble, and
  LMI sprinkles the documentation with  numerous  cautions  regarding  what  to
  watch out for.

  For openers, LMI includes a file access function word called FDOS that  gives
  you  direct  access  to 36 file operation primatives.  There are also another
  set of  extensions  that  "give  you  total  control"  for  record-level  I/O
  bypassing  the  FORTH  internal  disk  drivers  and virtual memory management
  features of the LMI FORTH altogether.

  LMI also supports binary overlays to link things like  the  editor  into  the
  dictionary as a one-shot.  This is described in the documentation.

  < COST-FREE TURNKEY APPLICATIONS >

  LMI provides several boot-up literals to  create  custom  pre-compiled  FORTH
  applications  using  this product.  No license fee is required as long as you
  seal-off the LMI F83 itself.  They would of course appreciate some credit and
  a phone call to make sure you sealed everything up correctly.

  < SIMPLE MULTI-TASKING >

  Z-80 FORTH includes simple multi-tasking support  for  up  to  10  background
  tasks.  LMI allocates CPU to these tasks on a round-robin basis.  In general,
  however, these tasks should not access the  disk  or  keyboard  and  must  of
  course leave the stack clean upon exit.

  < EXCELLENT DOCUMENTATION >

  The documentation is of excellent technical quality and content  -  something
  growing  rarer in these torrid days of user-friendly coloring books.  The LMI
  documentation has MEAT.  From the internals section describing the formats of
  the  dictionary  formats  of  things like colon and "CODE" definitions, right
  down to a real index, I am very pleased with the manual.

  Although I am not trying to scare away beginners, the documentation  and  the
  generous  extensions make this an excellent "hacker" FORTH.  I do not mean to
  suggest that the newcomer to FORTH is neglected in the LMI  manual,  however.
  In  fact,  the  manual  contains  an instructive and interesting "overview of
  FORTH" that is one of the most concise yet useful readings on  FORTH  I  have
  seen  anywhere.   It  does not make for light reading mind you, but ounce for
  ounce it may be some of the most useful text you may ever scan  in  terms  of
  putting the language as a whole into a nutshell.  The text would be extremely
  useful to the professional programmer who is just getting into FORTH.

  The documention also  includes  several  useful  appendicies  including:   1)
  "Coping  with the F83 Standard", 2) "Restrictions on an 83-standard program",
  3) "Checklist for Program  Conversion  to  Z-80  FORTH  3.0",  and  "Adapting
  STARTING FORTH to Z-80 FORTH 3.0".

  < USER SUPPORT >

  A word about support.  Once I called them for support and got handed off to a
  knowledgeable  analyst  promptly,  who  did  a  very  good job of fielding my
  questions.

  Another nice thing happened in my dealings with LMI  to  date:   I  purchased
  this product because I wanted a real FORTH for the Z80 and I noticed in their
  ad in FORTH DIMENSIONS a few months ago that it was still only $50.  Well,  I
  ordered it assuming (ass-u-me) that the ad price was right, and didn't verify
  this with the person who took my order (entirely my  stupidity).   Well,  the
  next  day my new issue of COMPUTER LANGUAGE came in the MAIL and the ad there
  pegged the LMI Z80 FORTH at $100.  Confused, I called LMI back  to  ask  them
  about it, and it turns out I did fubar it.

  LMI gave me a partial refund "to take some of the  sting  out  of  it".   Now
  THAT'S service !  Not to mention the fact that the product is quite worthy of
  it's $100 price tag.  Overall, I highly recommend the LMI  product  and  will
  consider  their version first when shopping for a FORTH for other processors.
  [rcs]