Apple II Serial Card
Here it is -- the first electronic thing I designed and built.
Obviously, this never made it to production. At this stage of my life, I
had no concept of entrepreneurship. What I did have was a need to send
and receive information and too little money to purchase a serial card, so my
only choice was to build my own.
I had an Intel 8251 somebody had given me and plenty of spare time. At
that time, semiconductor manufacturers were happy to send databooks to anyone
who wrote and asked for them (Long distance was expensive) and DigiKey and
Jameco were already in business, so all it took was some time with the
databooks and a career was born.
Every ten years or so, I tell myself I should go out to the shed, dig out one
of the old Apple IIs and see if any of them run. If one did fire up, I
could use my serial card to send all my old 6502 source files to a PC.
Why? I don't know. But the older I get, the more the idea
intrigues me.
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Hardware |
100% |
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Software |
100% |
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Processor |
6502 |
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Patents |
0 |
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70W RMS Per Channel Stereo Amplifier
In retrospect, despite mil-spec parts and hundreds of hours of painstaking
craftsmanship, it really sounds awful.
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Hardware |
100% |
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Software |
0% |
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Processor |
None |
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Patents |
0 |
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Stereo Preamp #1
As with the power amp, the quality per man-hour coefficient is exceedingly
low.
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Hardware |
100% |
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Software |
0% |
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Processor |
None |
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Patents |
0 |
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Stereo Preamp #2
This one sounds better, but it was never used as a real stereo. It
suffered from being too small, having no labels on the controls (other than
those scrawled onto the chassis with a pencil) and having no equalization on
the phono inputs.
It has a place on the shelf in the lab and still gets used now and then when
some non-critical signal needs a bit of amplification.
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Hardware |
100% |
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Software |
0% |
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Processor |
None |
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Patents |
0 |
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Telephone Call Logging Printer
This device prints the time, date and duration of every phone call placed on
the phone line to which it is connected.
Radio Shack expressed an interest in selling a stripped-down version of this
product, but the president of the company that built it refused to negotiate
the price. He wanted to get rich off the one deal with Radio Shack, and
when that deal fell through, his company went bust. Radio Shack
eventually had its own version designed, but it was not nearly as good as this
one.
Several Asian companies knocked off the whole design. They even copied
the aberration of the character "Z" in the dot matrix data, which was inserted
purposely to detect knockoffs (Z was never printed).
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Hardware |
100% |
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Software |
100% |
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Processor |
6502 |
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Patents |
0 |
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OCC Phone Autodialer
This is an intelligent Other Common Carrier autodialer and call router.
It is programmed with toll-free area codes and prefixes and decides whether
outgoing phone calls should be direct dialed or routed through the OCC.
Programming can be done with the local phone, a local computer via RS-232 or
remotely, using another dialer configured as a DTMF send modem. Once
programmed all blocking table and speed dial data can be uploaded to a
computer or cloned into another dialer.
If you look closely at the date on the EPROM, the firmware was last modified
in May, 2002. The board in the photograph is a spare, but a similar unit
has been in continuous service for the past 38 years.
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Hardware |
100% |
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Software |
100% |
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Processor |
6502 |
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Patents |
0 |
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Video Sync Restorer
Back when SD composite video was good enough, cable companies used to
scramble premium channels by removing the horizontal sync pulses. Using a
complex state machine, implemented with PLD logic, this board figured out
where the sync pulses belonged and reinserted them.
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Hardware |
100% |
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Software |
0% |
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Processor |
None |
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Patents |
0 |
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Prototype T1 Channel Bank
This is really two separate prototype cards screwed together for
testing. The card on the left is the T1 interface and status
indicators. The card on the right is the backplane timing generator and
one FXS voice interface. Several very intelligible phone calls were
placed through this crude device.
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Hardware |
100% |
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Software |
0% |
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Processor |
None |
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Patents |
0 |
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Channel Bank Power Supply
This is the power supply card for a T1 channel bank.
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Hardware |
100% |
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Software |
0% |
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Processor |
None |
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Patents |
0 |
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Channel Bank LIU
These are the LIU cards for a T1 channel bank. The two boards plug
together to form a double-wide module that occupies 2 slots in the backplane.
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Hardware |
100% |
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Software |
0% |
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Processor |
None |
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Patents |
0 |
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Channel Bank Dual FXS Card
This is a dual FXS voice card for a T1 channel bank.
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Hardware |
100% |
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Software |
0% |
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Processor |
None |
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Patents |
0 |
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Hydronic Heating System Temperature Fan Controller
Nobody made these at the time, so it was necessary to build my own.
This little board measures the temperature of the water pipe exiting the air
handler and turns on the FAU fan only when hot water is circulating.
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Hardware |
100% |
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Software |
0% |
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Processor |
None |
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Patents |
0 |
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Client Side Interactive Video Control System
Using a TV and the telephone line, this device allows compressed video and
audio subscriber information to be interactively presented on the TV.
Navigation is provided by the telephone keypad or an IR remote.
Needless to say, the Internet killed this technology in short order.
|
Hardware |
100% |
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Software |
100% |
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Processor |
x86, 6805 |
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Patents |
0 |
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Handheld IR Remote Control
The hardware was simple and basic, taking all of an hour to design. The
firmware took a couple more hours to write, producing in-house development
costs for electronics and software of less than $100. Several quotes
from Asian remote suppliers came in at 100 to 200 times that amount.
Mechanical engineering was another story, but I had no involvement in that.
|
Hardware |
90% |
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Software |
100% |
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Processor |
6805 |
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Patents |
0 |
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Universal IR Remote Decoder
This was designed as an IR remote receiver that would send decoded IR codes
to a PC though the serial port. It was used for sales presentations to
simulate the operation of a proposed product on a PC.
I modified the firmware so that it would decode any IR pulse stream and report
it to the PC as an ASCII packet, giving the period in microseconds between
each rising and falling edge.
The unit in the photo was pulled down off the shelf, dusted off and used to
decode some IR codes for a project in July, 2022, almost exactly 31 years
after its creation.
|
Hardware |
100% |
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Software |
100% |
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Processor |
6805 |
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Patents |
0 |
|
|
32-channel Async Daughter Card
This board plugs on to the ISA bus multi-protocol serial controller to
provide another 32 asynchronous RS-232 channels.
|
Hardware |
100% |
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Software |
100% |
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Processor |
x86 |
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Patents |
0 |
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T1 Serial Module LIU
This board stacks on the T1 serial module, disabling its CSU and providing
an FCC-approved long line connection.
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Hardware |
100% |
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Software |
0% |
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Processor |
None |
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Patents |
0 |
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T1 Serial Module
This board is used at the other end of the RS-485 link provided by the ISA
bus multi-protocol serial controller to form a T1 serial module. It can
be used alone to connect to a short line or stacked with the LIU module shown
below for long lines.
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Hardware |
100% |
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Software |
100% |
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Processor |
x86 |
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Patents |
0 |
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Dual High-speed Sync Serial Module
This board plugs on to the multi-protocol module serial controller to form a
2-channel high-speed synchronous serial module, providing 2 channels of HDLC
or bisync at up to 2.048 Mb/sec.
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Hardware |
100% |
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Software |
100% |
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Processor |
x86 |
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Patents |
0 |
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Quad Sync Serial Module
This board plugs on to the multi-protocol module serial controller to form a
4-channel synchronous serial module.
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Hardware |
100% |
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Software |
100% |
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Processor |
x86 |
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Patents |
0 |
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Octal Async Serial Module
This board plugs on to the multi-protocol module serial controller to form an
8-channel asynchronous serial module.
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Hardware |
100% |
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Software |
100% |
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Processor |
x86 |
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Patents |
0 |
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Multi-protocol Module Serial Controller
This board is used at the other end of the RS-485 link provided by the ISA
bus multi-protocol serial controller where intelligence is required. The
async, sync and high-speed serial boards shown below can be stacked on this
board to form a complete serial module.
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Hardware |
100% |
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Software |
100% |
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Processor |
x86 |
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Patents |
0 |
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ISA-bus Multi-protocol Serial Controller
This board acts as an intelligent hub for two 2.048 Mb/sec HDLC RS-485 links
which can be connected to a variety of serial devices.
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Hardware |
100% |
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Software |
100% |
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Processor |
x86 |
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Patents |
0 |
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RS-232 to RS-422 Converter
Sure, everybody makes these now. Back when this was created, there were
only a few companies making them and they were terribly expensive. My
client needed a cheaper alternative, so I whipped this out in a couple of
hours. Twenty of these boards could be built for the cost of a single
off-the-shelf equivalent.
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Hardware |
100% |
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Software |
0% |
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Processor |
None |
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Patents |
0 |
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|
ISA-bus 8-channel Digital Voice Card
This board provides 8 FXS central-office-quality POTS circuits on a single PC
plug-in card. It interfaces to other digital-voice components through a
proprietary interboard connection bus or an MVIP connector.
There was a 4-channel predecessor and the basic design was adapted to create
an FXO version. All cards can be configured for loop or ground start.
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Hardware |
100% |
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Software |
100% |
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Processor |
x86 |
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Patents |
0 |
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|
ISA-bus T1 Card
This was one of the first T1 cards available for the PC. It features
on-board DSU, time-space switch, proprietary interboard connection bus and
MVIP bus interface. This board was in production for well over a decade
and became the nucleus of several PC-based digital-voice products. Of
special interest is the external frame sync port, which allows the board
to be connected and synchronized to a wide variety of digital-voice and
channelized data devices. It can be the timing master or slave to the
external device, using any of three different frame-sync modes
Both the DSU and CSU build options of the board are shown.
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Hardware |
100% |
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Software |
100% |
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Processor |
x86 |
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Patents |
0 |
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Network MPEG-II Movie-On-Demand Set-Top Box
This device has allowed its manufacturer to add Digital Movie-on-Demand
to the list of capabilities of its proprietary high-speed daisy-chainable
network. On request from the user, compressed digital movies or other
audio/visual material can be supplied from a central server and viewed
through a normal television receiver any place on the network. When the
set-top box is turned off, normal CATV or antenna programming is
supplied to the TV.
|
Hardware |
100% |
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Software |
100% |
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Processor |
CPU32 |
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Patents |
0 |
|
|
Cellular Fixed-Station Adapter
This product was developed to bring telephone service to areas where the cost
of running physical copper wire is prohibitively expensive. It connects
between a normal telephone set and mobile cellular radio, emulating the
handset back toward the radio and emulating a central office toward the
telephone. Low cost was the primary design goal, which was met through
the innovative use an inexpensive 8-bit microcontroller and sophisticated
real-time software to generate all central office tones digitally.
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Hardware |
100% |
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Software |
100% |
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Processor |
6805 |
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Patents |
0 |
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|
ISDN U-Interface Drop-and-Insert Test Set
This is a one-of-a-kind product, which allows the ISDN developer to monitor
or log the ISDN U-interface D-channel or either or both B-channels in real
time without compromising the normal operation of the equipment connected to
the ISDN line. With proper PC software, the D or B-channels may be
inserted toward the central office, the user equipment or both, allowing
emulation or simulation of any equipment or events. Two RS-232 links are
available for connection to one or two computers to facilitate any conceivable
test situation.
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Hardware |
100% |
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Software |
100% |
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Processor |
68000 |
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Patents |
0 |
|
|
ISDN Terminal Adapter Power Supply
This produces all the voltages required to run the ISDN Terminal Aadapter
from a 15 VAC wall module:
- +5 volts for digital logic
- +5 volts for analog circuits
- -5 volts for analog circuits
- -28 volts POTS talk battery
- 86 VAC RMS 20Hz ringer voltage
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Hardware |
100% |
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Software |
0% |
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Processor |
None |
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Patents |
0 |
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|
ISDN Terminal Adapter
Central-office quality POTS ports, two multi-protocol data ports, with
software selectable RS-232, RS-422 and V-35 modes and bulletproof
highest-reliability hardware design distinguish this product from other
similar units. Firmware includes patented D-channel processing (US Patent
5,748,628), which offers total international switch-independent
operation with NO programming required. A rich feature-set, including
analog and digital caller ID, call-waiting caller ID, SMDR, EKTS, conference
calling, multi-way calling and a streamlined command interface devoid of those
cumbersome "AT" codes, all in 40 Kbytes of code, make this product unique in
the industry. Third party tests have shown consistently higher
throughput than competing units having microprocessor clock speeds as much as
50% higher.
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Hardware |
100% |
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Software |
100% |
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Processor |
68000 |
|
Patents |
2 |
|
|
T1/E1/J1 PRI D-channel Monitor
This device allows the ISDN PRI developer to monitor the D-channel messages
sent and received by any T1, E1 or J1 device having monitor jacks. Data
may be monitored in real time, logged to a PC and/or logged to onboard Compact
Flash.
Total development time, from conception to working product, was under 2
months. The first prototype board (shown in the picture) was fully
operational at first power-up, requiring no changes to hardware or
programmable logic.
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Hardware |
100% |
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Software |
100% |
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Processor |
68000 |
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Patents |
0 |
|
|
PCI Quad Comm Board
This was a hardware port of an existing ISA card to the PCI bus. The
goal was to maintain 100% software and hardware compatibility between the PCI
and ISA versions. I proposed an integrated version that would have been
cheaper and simpler, but the direct port was chosen because nobody wanted to
make any changes to the embedded code.
The layout guy used the wrong library part for the processor and I had to
"adjust" it on the first prototype (see inset image).
Otherwise, this was a boring and uneventful project.
|
Hardware |
100% |
|
Software |
10% |
|
Processor |
x86 |
|
Patents |
0 |
|
|
BDM to PC Parallel Interface
Background debug interfaces are typically top secret and ridiculously
expensive. This one is dirt simple, uses readily-available socketed DIP
parts and costs about $2.00 to build. Toss in a little top-secret
software for a DOS or Windoze PC and debugging occurs directly from the
assembly source listing files. Bugs are fixed before the massive,
expensive debugging system finishes loading.
|
Hardware |
100% |
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Software |
0% |
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Processor |
None |
|
Patents |
0 |
|
|
USB Digital/Analog Audio FM Transmitter
This board converts digial audio, passed from a PC though a USB connection,
to analog. The analog audio appears on line out (RCA) jacks and a
headphone jack. There is also an FM transmitter, which can transmit
audio content from the USB or line input jacks.
Unfortunately, funding was cut just before the first batch of prototypes was
to have been built, so the project was canceled.
|
Hardware |
100% |
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Software |
0% |
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Processor |
None |
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Patents |
0 |
|
|
T1 PRI D-channel Monitor
This device collects ISDN PRI D-channel messages and sends them, via
Ethernet, to an IP address obtained from a DHCP server. It can be
powered from an external supply or from the Ethernet line.
The first board powered up and ran, with fully operational debug
capability. No changes to hardware or programmable logic were
required. Less than one hour of software debug at the first Beta install
site and one firmware upgrade in the field resulted in a completely functional
unit.
|
Hardware |
100% |
|
Software |
100% |
|
Processor |
68000 |
|
Patents |
0 |
|
|
Hybrid-Electric Vehicle Dual Electric Motor Controller
This is a research prototype controller board for a two-motor hybrid
vehicle. It was created by the Big Car Company to determine the limits
of the technology and create a viable specification for the ultimate
supplier.
I was brought in to bring up the first board, create the critical ISR prolog
and epilog code and write start-up code and drivers.
|
Hardware |
0% |
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Software |
20% |
|
Processor |
PPC |
|
Patents |
0 |
|
|
Belt-Alternator-Starter Weak Hybrid Controller
This is a research prototype controller board for a weak hybrid vehicle,
utilizing Belt-Alternator-Starter technology. It was created by the Big
Car Company to determine the limits of the technology and create a viable
specification for the ultimate supplier.
Once this had been handed off to the supplier, the Big Car Company's bloat
code would not run because the supplier's prolog for the main control loop ISR
was taking 20us, leaving too little time for the task to execute. Their
story was this was the fastest it could possibly be. My code was taking
650ns, worst case, so, their incompetence exposed, they had to
reconsider. Eventually, they got it down to 12us, which was still
utterly incompetent.
|
Hardware |
0% |
|
Software |
50% |
|
Processor |
PPC |
|
Patents |
0 |
|
|
160KHz Switching Frequency Advanced Hybrid Vehicle Electric Motor Controller
This is an advanced project research prototype controller board for a hybrid
vehicle electric motor inverter using MOSFETs instead of IGBTs and having a
switching frequency of up to 160KHz. It was created by the Big Car
Company to assess the feasiblily of designing this technology into the next
generation of inverters. My role was to create all the code except the
controls. The key accomplishment on this project was synchronizing the
PWM and A/D converters to the control loop while they ran at any integer
multiple of the control loop frequency between 2 and 16.
|
Hardware |
0% |
|
Software |
100% |
|
Processor |
PPC |
|
Patents |
0 |
|
|
Hybrid-Electric Vehicle Bidirectional Charger/Inverter
This is an advanced project research prototype controller board for a
bidirectional hybrid vehicle charger/inverter. It was created by the Big
Car Company to assess the feasiblily of designing this technology into the
next generation of hybrid-electric vehicles.
I wrote all the code, which was necessary due to having the control loop run
at 50KHz switching frequency. The control engineers gave the algorithms and I
smashed them into the 20us available. The result was a multitude of patents awarded.
|
Hardware |
10% |
|
Software |
100% |
|
Processor |
PPC |
|
Patents |
8 |
|
|
Hybrid-Electric Vehicle 5-Phase Motor Controller
This is an advanced project research prototype controller board for a
hybrid-electic vehicle utilizing a 5-phase motor. It was created by the
Big Car Company to compare the costs and efficiencies of new 5-phase motor
designs to existing 3-phase motors.
The controller board was designed for a new dual-core processor and was going
to be used to control two motors with a single microprocessor, but due to
delays in production of the processor, the whole 2-motor project was on
hold. And because there was no funding available to design a new
controller for the 5-phase project, that project was also on hold. It
was my suggestion that a batch of 2-motor boards be built with the older,
single-core processor that got this program going again.
Bloat code from the control engineers caused the fast loop to run too
slowly. The algorithm I derived for fast estimatiion of a critical
5-phase control parameter during field weakening overmodulation led to my
first electric vehicle patent.
|
Hardware |
40% |
|
Software |
80% |
|
Processor |
PPC, eTPU |
|
Patents |
1 |
|
|
Hybrid-Electric Vehicle 3-Phase Boost Controller
This is an advanced project research prototype controller board for a 3-phase
boost converter. It was created by the Big Car Company to derive a
specification for a production converter that would increase the voltage from
a fuel cell or battery pack for the high-voltage bus in a fuel cell,
hybrid or plug-in electric vehicle.
Two patents were granted for optimizations of the control code and one was
pending for PWM generation when my association with the Big Car Company ended.
If this board looks similar to the one below, it is. Once again, it was
my suggestion to repurpose this same controller board for this project.
Otherwise, the Big Car Company would have wasted months and thousands of
dollars on creating a dedicated controller.
|
Hardware |
20% |
|
Software |
100% |
|
Processor |
PPC, eTPU |
|
Patents |
2 |
|
|
Hybrid-Electric Vehicle 2-Motor Controller
This is an advanced project research prototype to access the feasibility of
controling two motors with a single microprocessor. It was created by the Big
Car Company in a half-hearted attempt to take the next logical step in
electric vehicle motor control.
The prototypes performed well and I showed them how to adapt two instances of
their single-motor bloat code, produced on a Linux server farm (using a
process which has not changed since 1982), to run on a single processor.
But in the end the lawyers prevailed. It was determined that cost and
complexity savings were not worth the risk of having a single-point failure
take out both traction motors.
I did get a patent for my code merging scheme, however.
|
Hardware |
20% |
|
Software |
100% |
|
Processor |
PPC, eTPU |
|
Patents |
1 |
|
|
Internal Combustion Engine 58X Position Sensor Emulator
When you're a Big Car Company, you feel a need to control everything.
In the case of a hybrid-electric vehicle, you feel the need to control where
the internal combustion engine stops during shutdown so as to reduce vibration
on the next startup. If you're trying to get this working, you can't be
lugging an engine into the lab. What you need is a simple simulator.
The official decision-makers came up with a plan to saw the sensor wheel off
the end of a crankshaft and mount that on a bearing in a special fixture with
the reluctance sensor from the engine. That was a great plan (especially
for those who appreciate steam locomotives and Harley-Davidsons), but I needed
simulation now, not two years from now, so I designed and built a simple
little board that produced the signals with an 8-pin microcontroller.
|
Hardware |
100% |
|
Software |
100% |
|
Processor |
PIC |
|
Patents |
0 |
|
|
Hybrid-Electric Vehicle Motor Controller With Integrated Gate Drive
After ten years of screaming by the engineers at the research facility, the
Big Car Company decided it might be worth trying to build its own motor
controller instead of building prototypes and using them only to create a
specification to put out for bid. This is the result. It is
complex and overblown, but mostly better than what an outside supplier would
produce.
Then, to compensate for doing something right, the Big Car Company closed down
the research facility and integrated the work into its main powertrain
development, which happens in a place where it gets down to -20 degrees in the
winter.
|
Hardware |
0% |
|
Software |
100% |
|
Processor |
PPC, PIC, eTPU |
|
Patents |
0 |
|
|
Hybrid-Electric Vehicle Motor Controller With Integrated Gate Drive
This board has the same basic functionality as the one created by the Big Car
Company, but as a result of having been developed by a non-Big Car Company,
costs half as much and has a quarter the complexity.
Total software development time -- from nothing to fully functional and
capable of driving a vehicle -- was three months.
|
Hardware |
0% |
|
Software |
80% |
|
Processor |
PPC |
|
Patents |
0 |
|
|
Networked High-Intensity LED Lighting Controller
In need of firmware, the client came to me with existing hardware and the
idea of powering high-intensity LED lights over the CAT5 cable used to network
the lights together. It seemed like a weird concept, but software
doesn't care about that.
|
Hardware |
0% |
|
Software |
100% |
|
Processor |
PIC |
|
Patents |
0 |
|
|
High-Intensity LED Lighting Controller
This is a controller for a high-intensity LED light. It can control up
to four LED strings, receiving input from an ambient light sensor, a motion
detector, a 10-volt analog dimmer, IR remote, RS-232 or RS-485.
|
Hardware |
20% |
|
Software |
100% |
|
Processor |
PIC |
|
Patents |
0 |
|
|
Digital PIR Motion Sensor
This is a motion and occupancy sensor for controlling an LED light. It
is fully digital, using a microcontroller to sample the voltage output from
the PIR sensor and detecting motion algorithmicaly. Utilizing the
onboard asynchronous serial port, it can report status and have its
operational parameters adjusted.
|
Hardware |
20% |
|
Software |
100% |
|
Processor |
EZ8 |
|
Patents |
0 |
|
|
Old-School LED Digital Clock
And so we come full circle...
If you can't buy what you want, build it.
- LED display for absolute brightness control
- Ambient light level brightness tracking
- Incrementally increasing alarm volume level
- AC power for reliable 60Hz reference
- RS-232 debug/status/programming interface
- No batteries (except for timekeeping during power outage)
- WWVB receiver
- Proximity sensor alarm control
- Simple and quick user interface
- Endlessly programmable forever
- Night vision brightness compensation
|
Hardware |
100% |
|
Software |
100% |
|
Processor |
PIC |
|
Patents |
0 |
|
|
Hydronic Heat Controller
It is an unfortunate reality—even after many decades of this viable
technology—that any hydronic heating system must be assembled from bits
and pieces, sourced from many different manufacturers. Consequently,
there are no controllers available that understand the negative hysteresis
required to implement temperature-based blower trip points.
This board works well as a hydronic pump and blower controller, extracting
maximum heat from the exchanger, but it was actually designed to be a
general-purpose controller for any heating/cooling application, featuring four
optically-isolated inputs, four solid-state relay outputs and significant
breadboard area. The unit in the picture has been retrofitted with a
thermistor/ADC interface and flashing LED to indicate controller state.
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Forced-Air-Unit Monitor
If this looks a lot like the Hydronic Heat Controller, that's because it is
the same board, repurposed when the heat exchanger in the hydronic air handler
sprang a leak and the whole hydronic unit was replaced with a conventional
forced-air heating unit.
New firmware was loaded into the controller and the board wired to the
thermostat, in parallel with the FAU. With the board connected to a laptop,
running software written to decode the simple serial data stream output by the
monitor, every heat cycle is recorded with millisecond resolution.
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LED Digital Thermometer
If you can't buy what you want, build it.
- LED display for visiblity at night
- Hard-wired exterior probe for no RF
- Probe power and data on two wires
- Full digital probe interface
- Multiplexed display for minimum power consumption
- Ambient light level brightness tracking
- AC power for no dead batteries
- RS-232 debug/status/programming interface
- Simple and quick user interface
- Endlessly programmable forever
By leveraging many design elements from the Old-School LED Digital Clock, this
project went from concept to working prototype in three weeks.
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