Resumé of Embedded Controller software development work -  1975 - 2000
performed by Ted Knowlton
a little personal history

49 Stonehedge Road, Lincoln, MA 01773  781-259-0425  ted@tedknowlton.com

Summary of skills:
All my embedded controller projects have been developed with very compact assembly language.  Throughout the past 25 years I have developed a broad group of routines for a wide variety of controller applications.  My forté is making electro-mechanical devices work.
Member IEEE.

Chronologically from 1975:

1975 - 1977  at Control Logic (div of Harnischfeger Corp.), Natick, MA

Designed and wrote Intel 8085 assembly code to control P&H automated warehouse bridge cranes.  Completed installations at DuPont (Charleston, SC) and Alcoa (Evansville, IN).  The Alcoa installation included two huge bridge cranes for moving, storing, and maintaining inventory of big blocks of carbon used in making aluminum.  Each crane had its own micro to control 3D motion, and the cranes were controlled (via serial link) from a user interface in a remote ground console (CRT).  Just one control program alternated between the two cranes.  The project was featured in "Digital Design", November 1977, pages 78 - 84.
1977 -1978 at Gould-Modicon, Andover, MA
Designed and wrote 8085 code for testing P-180 Programmable Controller.  Peripheral chips included DMA and CRT controllers.
1978 -1980 at Nova Biomedical, Waltham, MA
Designed and wrote 8085 code for controlling stepper motor driven "sampler-printer".  Project included development of communication protocol with blood analyzer micro, character generation and control for a thermal printer; project included many hardware/software safety checks.
1980 - 1992 at NEC Electronics, Inc., Natick, MA
1980 - 1984 Applications Engineer - Single-Chip Microcomputers
1984 - 1992 Senior Applications Engineer - Digital Signal Processors
Developed hardware/software application and wrote application notes to assist customers in the use of NEC chips in their product designs.  Single-Chip routines included key scan/debounce, LCD updates, up to 64-bit floating-point math, clock/calendar, A/D input, etc. for 4- and 8-bit micros.  DSP chips included 16- and 24-bit fixed point and 32-bit floating point devices.  Significant DSP application notes: "Basic Hardware Interface and a Frequency Measurement Implementation," "Data Acquisition and Digital Filtering" (16-bit DSP), and "Data Acquisition, Digital Filtering and Spectral Analysis" (32-bit f.p.).

When first hired at NEC, I wrote software for customer applications (AC Nielsen, various toy manufacturers, Motorola Microwave Oven controller for Amana).  Later on, NEC stopped the practice of customer application development; however, I was grandfathered into this practice, and I continued to moonlight.

Computer Controlled Precision Piano Tuner
While working at NEC I pursued, on my own, a project of my own design which included most of my past experience with digital control and lots of new experience with Digital Signal Processing.  Click here to read a paper presented at a 1992 DSP conference.
This complex device was demonstrated in 1996 at a Piano Technicians Guild seminar.  The device works, but is too cumbersome in its present embodiment.  The project remains on the "back burner" and will resume when better methods are determined.


Consulting Projects:

1983 Distance Measuring Computer, NEC 4-bit micro controls this hand-held device using sonar transducer and timed echo.

1984 - 1988+ American Stabilis (ME), NEC 4-bitter for a "smart" thermostat with a host of programmable features stored on EEPROM.

1988 - about 2002 designed and developed software for a line of hand-held precision laboratory pipettors for Matrix Technologies (Hudson, NH).  User programs, stored in EEPROM, control a variety of sequenced stepper motor moves. An NEC 4-bitter controls these products which have LCD and complex calibration subfunctions, floating point math. Designed program for transferring test results into a special Excel program for quality control statistical analysis.

1994, 1995  for Omega Engineering (Stamford, CT), designed 4-bit software for hand-held infra-red pyrometer.  Functions included 4-bit software for successive approximation A/D, pulse-width modulated output signal, f.p. math, continuous serial communication with PC for data logging.

1995 NEC America (Irving, TX) 4-bit user-interface for digital cellular phone.

2000 Fishman Transducers (Wilmington, MA) started but did not complete project for user interface on a digital musical instrument device using Motorola 8-bit flash memory micro.  Flash memory allows field upgrade of product via serial link to PC.