Thinking Forth
by Leo Brodie

First posted
Monday January 17, 2011 07:39
Tuesday March 1, 2011 08:50


Tuesday March 1, 2011 08:37

Thinking Forth by Leo Brodie is subject of our interest.

Page 263

Jerry Boutelle photographed at Henry Neugass's home in Mountain View, CA shorly after we completed the 8080 Forth port to the 8051 in the mid 1980s.

Payne's Sandia labs badge can be seen clipped inside case seen at left.

Photo located Tuesday March 1, 2011.

Embedded Controller Forth for the 8051 family
Windows 2000, XP, and 7
USB/Serial interface
ExpressSCH/PCB surface mount
SCADA Forth51 boards
web lectures

Datatron 205, IBM 1401, Sinclair ZX81, Jupiter ACE, Basic52, Thinking Forth 1984, 2004 - Friday January 21, 2010 15:37.

MCS BASIC-52 REFERENCE MANUAL posted Sunday January 23, 2011 08:07

  1. Page 2.

    Other machines did not.

    Datatron 205 was a Binary Coded Decimal machine with signed 10 decimal number. Programs were stored on a rotating drum memory.

    Vacuum tube replacement for Datatron cost Purdue University about $50k/year in last years of its use.

  2. Page 31

    This depends of the Forth assembler.

    High-level Forth checks syntax in the sense it clears the 'smudge bit' if a : ; definition compiles.

    Smudge is documented in Forth Encyclopedia by Derick and Baker.

    Smudge demonstration hide video.

    Assembler syntax checking hidef video.

  3. Leo Brodie writes on page 164

    'After many years someone realized that the nicer name is WORDS.'

    Where's the documentation? Let's see it work on an 8080 system.
    Jerry Boutelle warned us that most Forth variations, especially the forth 'standards' such a 83, should be avoided because they offer only changes, not improvements, to fig-Forth. And that people involved in creating forth 'standards' should be avoided.

    on page 234

    and on page 239

  4. Embedded Controller Forth for the 8051 Family author writes

Wednesday February 2, 2011 08:38

Windows On ARM: For Intel (And AMD And Via), Probably No Cause For Alarm


Saturday January 29, 2011 07:51 

Clocks, Egyptian Windows XP, Windows Explorer proves C for embedded controller apps sucks and Forth attempted destruction by standards saboteurs. - Tuesday January 25, 2011 15:05

More Clocks, countering bad-mouthing fig-Forth, Android conference - Wednesday January 26, 2011 14:19
Stanislaus Ulam is the name instructor was blocking on in above lecture.


Ulam at console of Los Alamos Maniac computer.

We will use John vonNeuman's Princeton architecture in our 8051 family surface mount Forth 51 machine.

vonNeumann and daughter Marina on the plaza in Santa Fe, New Mexico.

The Monte Carlo method came into concrete form with its attendant rudiments of a theory after I proposed the possibilities of such probabilistic schemes to Johnny in 1946 during one of our conversations. It was an especially long discussion in a government car while we were driving from Los Alamos to Lamy.

S M Ulam
Adventures of a Mathematician
Charles Scribner's Sons 1976

Oscillator circuits, Frequency vs power consumption, dynamic and static 8051 family parts, conversation with Jose - Thursday January 27, 2011 10:17

Basic52 manual in html posted.


Scanned Tuesday January 25, 2011 

Setup and Hold TIme.

Revisiting the good ol’ setup and hold violation.

Thursday January 27, 2011

Vss is ground. See pin 20 on 8051 dip package above.

The faster the part runs, the more power it consumes.

Dynamic part - minimum oscillator frequency.

Static part - from DC, no minimum frequency.

Forth51 is running under HyperTerminal in 64-bit Windows 7 using Belkin USB/Serial adapter HiDef video!

Reset, Forth51 works under Windows 7 64-bit - Friday January 28, 2011 11:37


Two types of resets.



Embedded Controller Forth for the 8051 Family motherboard implementation.


Embedded Controller Forth for the 8051 Family motherboard implementation.

The push button is located on a daughter board call the maintenance support board.

Both cause

Both cause Forth51 to do the eqivalent of 8080 Forth

Reset 10 ohm resistor, connector selection, Kinetis Austin seminar, All sections will feel aftershocks on Windows-on-ARM shift - Tuesday February 1, 2011 13:22

Instructor is not happy with below HiDef video. But it may be instructive.

Forth51 HyperTeriminal 64-bit, board connectors - Tuesday February 1, 2011 13:22

Tuesday February 1, 2011 11:15

Reset voltage levels

.7 * 5 = 3.5 volts or more to cause reset.

must be observed.

Instructor is not happy with below HiDef video. But it may be instructive.
Forth51 works with Belkin 7 port USB Hub under XP, Kinetis software development tools - Yuk - Wednesday February 2, 2011 11:08

Mini lecture 1 - Thursday February 3, 2011 09:17

Mini lecture 2 - Thursday February 3, 2011 09:17

Mini lecture 3 - Thursday February 3, 2011 09:17

Mini lecture 4 - Thursday February 3, 2011 09:17

Mini lecture 5 Silicon Labs C8051F32 X tentatively selected for initial board build - Thursday February 3, 2011 09:41

Friday February 4, 2011 13:59

We are also looking at CY7C68013A, CY7C68014A, CY7C68015A, CY7C68016A.

High speed USB is not as important as having -PSEN, -RD, -WR, RESET, D0-D7 and A0-A15 pins.

Cypress CY7C68013 part selection reasons, oscillators, Winbond 78C32V-40, oscillators, Netchip 2270 lecture - Friday February 4, 2011 14:39

CY7C680xx datasheets. 128 pin quad flatpack.

No ALE for reason that D0-D7 and A0-A7 are not multiplexed.

Note that -PSEN, -RD, -WR, RESET are connected.

Here are essential Forth51 pins only brought out on 128 pin package.

cy7c68013. Note that they are all ROMless.

Cormac Sookram, former employee of Cygnal, helped us get Cygnal development system working.

Two lunches with Sookram on Guadlaupe st in Austin were fun.

But we got Cygnal's number.

Cygnal parts were merely USB 2.0 compliant but only low and full speed.

That's why we went with Netchip 2270.

Silcon Labs/Cygnal chips do not support Von Neumann [Princeton] architecture, only Harvard.

Cypress 128 pin packages do both.

Table 1.

Referenced in 205 email.

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