Microcontroller Programming

Dar Scott provides programming services for embedded computers and microcontrollers.

Background

Over the years Dar Scott has written embedded applications for PIC18, 8051 (of many variations), 6502 (of several variations), 68HC11, Z-80, 4040, 8080, x86, 6800, 6809, and 68000 microprocessors. In recent years most of the code has been written in C and assembler. In addition, as part of the software development, Dar Scott has programmed the surrounding logic using FPLA and CSoC technologies.

Dar Scott has written I/O code for serial port controllers, floating point modules, clock/calendar chips, D/A & A/D modules, IEEE-488 controllers (GPIB), parallel I/O boards, video boards, motor controllers, relays, power supplies, multiproccessor communications, tcp/ip drivers, STD boards, PC104 boards, optical sensors, timer boards, switches, scatter sensors, scanners, SPI bus, multiplexors, plotters, CCD arrays, tape drives, temperature sensors, thermocouples, current probes, IR receivers, RTCs, external serial memory, USB interfaces, telephone interfaces, telemetry devices and special memory devices.

Dar Scott has written applications for a variety of scientific and technical needs. These involve wavemeters, spectrometers, laser controllers, dye laser controllers, display controllers, microdensitometer controllers, welling logging instruments, telephones, hearing aid experiment controllers, IR transceivers, laser environment monitors, monochrometers, photomultipliers, power-line loggers, power-line status units, microscopes, large electric motors, gas leak detection, X-Y tables, power supplies. These were for these industries: mining, power, defense, medical, semiconductor, optical, automotive, entertainment, physical security and standards.

Selected Microcontroller Projects

IR Receiver. For Canela Software, Dar Scott designed and programmed a flexible general purpose IR receiver with low part count, USB interface, mutual authentication, built-in diagnostics, updatability, feedback brightness customization, optimized system optics, and power management. A robust LiveCode stack library to communicate with the device and software to burn flash through an FTDI FT232RL USB-to-serial interface were also created. Tools included LiveCode, the HI-TECH compiler, optics software and Eagle. The PIC 18F24K20 MCU was selected for this design.

Well Logger Library. Besides the well logging hardware and software developed in the 20th century, Dar Scott created for Perma Works a general purpose communications, memory management and I/O library for the company's latest geothermal well logging probe. Tools used included SDCC (compiler), and Silab's USB debugger, and (for testing) LabView and LiveCode. The Silicon Laboratories C8051F351 was used.

Hearing Aid Placebo Controller. For General Hearing Instruments, Dar Scott provided interface consulting and firmware programming for a manager processor for volume control and power management for a hearing aid used in research. This included the development of an advanced touch-sensor methodology and the setup of verification hardware and software. Tools used included SDCC (compiler), and Silab's ToolStick, and (for testing) a ZeroPlus logic analyzer, LabView and LiveCode, along with a lab full of equipment. The Silicon Laboratories C8051F931 was used and several were burned by Dar Scott for a short production run.

Monochrometer Controller. For an instrument manufacturer, Dar Scott designed the software for a controller in a monochrometer. The system featured enhanced communications and computer control capability, special commands for manufacturing and calibration, and advanced stepper motor slewing functions. This required intimate knowledge of the mechanical systems, the electronic systems and the physics of the product. This project involved C coding, assembler coding (68HC11), project management & supervision, software design and review of electronics design.

Three Phase Fault Generator. Dar Scott designed and created a microcontroller based three-phase fault generator used for testing fault-logging and fault-handling equipment. Care was required for accurate frequency and phase representation. The project included packaging design, electronics design, board layout and microcontroller programming.

Pulse Wavemeter. For Sandia National Laboratories, Dar Scott developed the software and detailed analysis methods for a microcontroler based instrument for measuring the wavelength of short monochromatic pulses. He ported much of this code to to another MCU for an instrument manufacturer who obtained the license for manufacturing the instrument.

Three Phase Analyzing Logger. For J&M Systems, Dar Scott developed an instrument used in the power industry. This involved multiple processor cards and I/O boards on the same SPI bus with fast and reliable communication software and hardware. Special considerations involved maintaining sustained accurate measurement periods while making in-depth calculations and logging to floppies. Software provided the accurate measurement of phase, frequency, RMS voltage, fault parameters and transformations such as "symmetrical components."

High Power Laser Control. For Electro-Optical Systems, Dar Scott wrote software and selected I/O electronics for one controller and part of another for a high-power YAG laser. Hardware included 8051 processor boards, custom timing test boards, parallel I/O boards, GPIB boards, RS-485 boards and thermocouple boards.

Telemetry Interface. For Modular Integrated Technologies, Dar Scott wrote the software and programmed the surrounding programmable logic for a telemetry interface with precision timing requirements. The unit interfaced with the computer via RS-232. All connectors had status indicators and the system provided a wide range of diagnostics features.

Lab

Dar Scott has an extensive electronics lab for supporting microcontroller and embedded computer projects with particular I/O needs.