Bit Of History

CEBus is a home automation communications standard sponsored by the Consumer Electronics Group of the Electronic Industries Association and written by a committee made up of representatives from most of the major and even more of the not-so-major companies involved with consumer electronics, telephones, computers, and alarm systems. Some names of those involved (both directly and indirectly) that spring immediately to mind include Panasonic, Sony, Leviton, Universal Electronics, Johnson...

Variety Of Requirements

Rather than beat this theory into the ground, let me go back to the system I'm connecting to the ADIO board and analyze what signal conditioning is required. Table 1 shows the eight analog inputs I have designated and the temperature voltage ranges I'd like to measure. The next obvious question is how do I measure these temperatures. Do I use thermocouples, RTDs, thermistors, or what My answer is yes. In reality, given the ranges I've listed, there are quite a few options. You might even choose...

Article Software

Software for the articles in this and past issues of The Computer Applications Journal may be downloaded from the Circuit Cellar BBS free of charge. For those unable to download files, the software is also available on one 360K IBM PC-format disk for only 12. To order Software on Disk, send check or money order to The Computer Applications Journal, Software On Disk, P.O. Box 772, Vernon, CT 06066, or use your VISA or Mastercard and call (203) 8752199. Be sure to specify the issue number of each...

Attached Product Operational Modes

The SMART HOUSE system accommodates a wide range of attached product complexity. In order to provide for differing levels of operational complexity and reduce require ments for electronics within these products, the control communications system supports four product operational modes conventional, simple, normal, and complex. Simple, normal, and complex attached products are collectively referred to as SMART appliances. Their capability to communicate with the system controller distinguishes...

Ax Dx

The right floppy in the drive before you start. So here's the process briefly. Set up your '386SX board, build that little LED and switch board, copy the appropriate boot record and COUNTSLO.BINtoafloppy,popitinto the '386SX's drive, hit reset, and watch the lights. That's all there is to it. Welcome to the wonderful world of embedded '386SX programming, minus all the aggravation and hocus-pocus you expected. It's all downhill from here The BBS files include several other simple programs to...

Basic

The BCC52 Computer Controller is Micromint's lOttest selling stand-alone single-board microcom-iuter. Its cost-effective architecture needs only a lower supply and terminal to become a complete levelopment or end-use system, programmable In IASIC or machine language. The BCC52 uses fcromint's 80C52-BASIC CMOS microprocessor fhich contains a ROM-resident 8K- byte floatlng-oint BASIC-52 Interpreter. The BCC52 contains sockets for up to 46K iytes of RAM EPROM, an Intelligent 27641128 PROM...

Basic Stepper Motor Construction

There are three main types of stepper motor construction variable reluctance, permanent magnet, and hybrid. The variable reluctance motor has a soft iron multitooth rotor. The rotor's closest tooth is attracted to the motor's wire-wound stator poles when a coil is energized. Because the rotor has no magnetic qualities, there is no attraction (detent torque) holding the rotor still while no power is applied, although it's capable of high step rates. The permanent magnet stepper motor has a...

Bipolar Versus Unipolar

Bipolar stepper motors are wound once on each stator pole. The magnetic polarity of the stator pole is switched by reversing the current in the coil. This reversing requires the use of a bipolar power supply or an H-bridge. It has higher torque (the complete coil is energized), but must use a more complicated power supply. Unipolar stepper motors have double windings on each stator pole, one in each direction. Switching the magnetic polarity of the stator pole is accomplished by simply...

Booting Firmware

In my very first Firmware Furnace column, I described firmware as a kind of epoxy mix the right combination of hardware and software and wait for it to set up like a rock. Although 805 1 firmware is usually associated with EPROMs, there's an easier way to inject firmware into our '386 system board-a floppy drive. Think of it as squishy firmware. You may feel as though you're cheating, but the all-in-one I O board I mentioned previously is under 40 (much less, in some cases), and a 3.5 floppy...

Call

AX, WORD LOW HiddenSectors DX, WORD HIGH HiddenSectors start with zeros account for sectors in both copies of the FATs boot sector and other . . . hidden sectors save start of dir set up parameters set up target and get one sector find sector address of data area just after directory we use directory size in bytes rounded to next whole sector entry size in bytes times entries round upward by sector size 1 find file's starting sector from cluster number MOV AX , ES BX+Di rEntry . Fi 1 eSta rt...

Cfm Temp Ps1 Setpoint

24 tines of Programmable Digital I O > 8 Channel, 8 Bit A D Converter > - 12 Bit counter > Includes Software and Manual > Addressable-Connect up to 32 on Single Multi-Drop Serial Cable Switch Selectable Baud Rates > Up to 60 Conv s (4.5 digit) - Add 40 for Virtual Instrument Software and PC Cable

Chan7

Table l--The eight analog channels of the ADIO board allow plenty of points to be measured to gef a good feel for temperatures In and around the solarium. LCD display, infrared remote control, badge IDs, analog 1 O, digital I O, and so forth. Up to 3 1 of these links can be connected to the SC. The ADIO-Link is particularly suited to this data-logging task. It has eight 8-bit analog inputs (0-5 volts), four 8-bit analog outputs (optional, 0-5 volts), and 24 digital I O bits divided as 16 inputs...

Cheap Time

With all the real-time clock chips on the market, you may still find the need to play it cheap. Cheap usually means using a software-based approach because apparently the word's out that software doesn't cost anything. Therefore, given the proper timebase, you can set up the required software timers to divide down the master clock successively into the elements that comprise real time as we count it. Of course, what you have may not be what you need, so you may have to do a little front-end...

Choosing Sensors

If you compare the list of six temperature ranges that I want to monitor in the solarium with the five types of sensors, you'll note a considerable overlap. Except where a specific accuracy or range limitation is the ultimate designator, choice of a particular temperature sensor is often just that personal choice. The list of six temperatures has two categories high temperature and low temperature. The four low temperatures to be sensed have a cumulative range of -20 F to 300 F. The two...

Commodity Computers

The 8031 was designed (about 15 years ago ) as a microcontroller for projects that handled a few variables, communicated slowly, and didn't need much code. That it's still in use today is a testament to how well the designers did their jobs. For small projects you just can't beat an 805 1. It is cheap, available on standard boards, and you can persuade it to do useful work quite easily. The catch is that you can design yourself into a corner where the next increment of performance costs much,...

Communications Protocol

The control communications subsystem distinguishes between control and communications information. Control information includes appliance status, diagnostic, power control, and other discrete (1 byte or less) information. Communications information is defined as the passing of Core Language messages and associated data. A transport layer protocol ensures the accurate delivery of message packets. A proprietary application layer protocol handler implements the Core Language and executes commands...

Conclusion

The tiny size of this interpreter amazes me. It has less than 5K of 80x86 object code, including all the methods. A lot of implosion occurred during development. I later rewrote the whole parser, complete with a half-dozen methods, in only four pages of 805 1 assembly language In the assembly language version, I was able to put the method address in the context list, eliminating the need for the method table array. Over the years, I have embedded tiny languages in many projects, resulting in...

Contact

Maxim Integrated Products 120 San Gabriel Dr. Sunnyvale, CA 94086 (408) 737-7600 Kingbright USA 22S Brea Canyon Rd. City of Industry, CA 91789 (714) 468-0S00 S301 Stevens Creek Blvd. P.O. Box 58059 Santa Clara, CA 95052-8059 (800) 752-0900 NBS-10 Interface Card provides gateway to network NBS-10 Interface Card provides gateway to network

Core Interpreter

The core interpreter, c a 1 ,C, contains only 18 1 lines of code. This file contains four externally callable routines c a 1 Pa r s e parses a token, c a 1 Ev a 1 executes CAL code, cal GetArg gets an argument for a method, and c a 1 De r ef looks up a variable. The parser, calParse, isa small routine that switches based on the next code byte. The parser uses calPtr.msgasapointertothenext code byte. As it reads bytes, it increments ca 1 P t r . ms g and decrements ca 1 P t r . 1 en. It puts the...

Core Language

The SMART HOUSE Core Language is an application layer protocol that exchanges commands, responses, and notifications between an appliance and the system control ler. The language includes over 100 message types, each performing a specific function. Using the Core Language, complex mode appliances can request system services such as the following Obtaining the time and date Controlling power delivery at outlets Communicating with other appliances Assigning switches to outlets or hard-wired...

Cross Development

Extensive arithmetic and logical operations Powerful macro substitution capability Selectable Intel hex or Motorola hex object file format Ten user-definable screens Unlimited breakpoints and memory mapping Trace file to record simulator session > Automatic substitution of defined label names for all jumps anc , Automatic insertion of supplied comments and expressions Broad range ot processor specific tools Intel, Motorola, Zilog, RCA, Rockwell All products require an IBM PC or compatible, MS...

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Deluxe Timekeepers

Although cheap is at times good, and a simple approach is preferable to a complex one, considering a more sophisticated tactic when evaluating peripheral functions for use in embedded designs is beneficial. This consideration is particularly advantageous when you can place multiple functions onto a single chip or, as in the case of real-time clocks, you can include typical support components in a single module with the timekeeper all set up and ready to roll. For example, I usually favor a...

Digital

1DC-I6A D converter (16 channel, 8 bit) 99.9S iput temperature, voltage, amperage, pressure.energy sage, energy demand, Tiglt levels, joystick movement and wide variety of other types of analog signals. Inputs may 9 expanded to 32 analog or 126 status inputs using the D-to or ST-32 expansion cards. 112 relays may be introlied using EX-16 expansion cards. Analog inputs ay be configured for temperature Input using he TE-P mperature Input conversion. RS-422 available. PS-4 pon ilector may be used...

Embedded Techniques

Embedded systems rbenefit from their capability to keep time. Often the capacity to do so is a requirement. As usual, you can keep time primarily through either a software-based approach or with hardware (implanting an electronic timepiece into the system in question). Through the use of a software-based clock, you can keep system overhead to an absolute minimum, an important consideration. At the other end of the extreme, parts exist that contain all of the constituents required to implement...

Encyclopedia For Configuring Motherboards

Thousands of main computer boards in service today have wide disparities in their configurations and jumper settings. More than 80 of these boards don't have the Original Equipment Manufacturer's name. When repairing such boards, technicians often had two choices blindly alter jumper settings until they get it right or sell the customer a new motherboard. Micro-House has added a third option with their new Encyclopedia of Main Boards. The Encyclopedia of Main Boards includes diagrams of all...

Express Circuits

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Feature Article

There are a number of home automation technologies vying for market share. SMART HOUSE was developed as a proprietary system initially aimed at new construction. Find out just what makes SMART HOUSE tick. is a complete *enabling system that rprovides the common resources needed for home automation in a multiproduct, multivendor environment-a system controller, a housewide wiring network, communications protocols, standard interfaces outlet designs for connecting other products, and basic user...

From The Bench

That's right, just a little closer. You don't want to miss this amazing offer. You say you have positioning problems (Get away from me kid, ya bother me.) Have I got the cure for you. Its not an ointment. Not a cream. Not even the ever-popular Elixir of Life. No friends, its the all powerful stepper motor translator driver. Yes, I can see the pshaw starting to form on all those lips, even as I speak. Well, let me assure you, you won't believe how easy movement will...

Gain Offset 0v

Figure 5 The same signal conditioning circuit can be used for all the channels with some minor tweaking. The gain (first stage) and offset (second stage) are set by the values of two resistors and some trim pots. How much you want to do is open. I designed the thermocouple signal conditioner to provide basic information. In my system, its 0-5-volt output goes to a second conditioner (gain 1 and offset 0) and then to the HCS. Connected this way, I can choose to either tweak the signals with...

General Software

Tel. (206) 3914285 Fax. (206) 7464655 (J The Snooper are Itadcrnarks of General Sollware Iric Tel. (206) 3914285 Fax. (206) 7464655 (J The Snooper are Itadcrnarks of General Sollware Iric HOUSE L.P. assigns object class-name and object identifier codes. The manufacturer specifies the messages a particular appliance such as a VCR) can receive and respond to. These messages can be listed in a data sheet for other product manufacturers' information.

Global Variable Declarations

CalPtr * main set of pointers * cal Ret * returned value * cal ContextLi st * the context list * calVarList * the variables list * calContext * current context * calObject * current object * ******** GLOBAL FUNCTION DECLARATIONS ********* calTokenType calParse(int, int) calTokenType cal Deref ( unsi gned short)

Got0 290

The gear ratio magnifies the torque (neglecting the efficiency of the transmission). This process is an important tradeoff when designing with a stepper motor. As a poet once wrote, in this world, nothing is had for noth-ing l . The trade is speed for torque or torque for speed. Any stepper has a maximum step speed and torque. You must determine the characteristics necessary of a stepper motor before you can choose one to do the job.

Home Automation System

Ademco Device Manufacturing Co. announces a home automation system that fully integrates with a professional security system. The Home Automation System links with Ademco Device Manufacturing's VISTA system to provide professional home security with telephone, lighting, appliance, and temperature control. The Personal Home Director and remote control devices known as Room Directors operate the system. A synthesized voice with 2,000 to 3,000 phrases guides the user through the system setup and...

Home Control System

Expandable Network IR Interface Digital and Analog I O Remote Displays To order the products shown or to receive a catalog, call (203) 875-2751 or fax (203) 872-2204 Circuit Cellar Kits 4 Park Street Suite 12 Vernon, CT 06066 140 and reuse the schedule by simply redefining a new starting point. You also can count over 45 days' worth of minutes using a 16-bit integer to schedule one month's activity without overly burdening an 8-bit processor. With this scheme, a typical schedule might consist...

Homework

If you're like me, your PC knowledge slipped while you were working with diddly little CPUs. There's nothing wrong with that, but you can't specialize in one thing forever Buckle down and do some research while you await your hardware. The good news is that the PC is no longer uncharted territory, so much of what you need to know is ready for the reading. I've collected a list of my favorite books in the Homework but surely I've missed some of the good ones. The bad news is that these weighty...

I

Attach eight LEDs and eight switches to the I O board's printer port. A '386SX is about one megaton of overkill for an LED blinker, but at least you can see if the program works Listing 4 shows how COUNTSLO . A SM displays a counting sequence on slowly enough to be visible to the naked eye. I used the BIOS WA I T routine to delay between counts there's a wealth of handy routines in the BIOS code and letting them go to waste would be a shame I used Borland's...

1

Fact, without the hyphen, no patents match this request.) Now, let me describe the abstract. Pressing F5 flashes the actual abstract itself on the screen, as is shown in Figure 1. Notice that more than just the text of the abstract appears. At the top is pertinent information about the patent, which includes the patent number, date of issue, date of filing, the name of the inventor(s), and the assignee (usually the company that sponsored the inventor). Also listed are references cited by the...

R S

Add Some Temperature Sensors to the HCS II kinds of cute titles ' could have used to introduce this article, such as Where There's Smoke, There's Fire or Wood Burning A Technical Dissertation. Authors often choose titles tongue in cheek, referring to their work with a sense of humor. Perhaps if I were writing for a literary journal rather than a computer reference magazine, I could still get away with it. Way back in the early days of BYTE I had a tendency to pick obscure titles. Would you...

Ic The Light

What you need is a chip that combines the high-current drivers, refresh logic, and an ASCII lookup table. Lucky for you, Maxim has just announced the MAX7219. Conceptually, the chip works the same as the CPU-based driver transistor setup. Eight-segment drivers connect to all the LEDs in parallel, with eight-digit drivers enabling individual displays. The '7219 has a built-in oscillator for refresh timing. It eliminates your worries about flicker because the oscillator runs at about 10...

Implementing

Space prohibits my listing or describing all the contexts, objects, and methods defined in the specification, but I will tell you that methods exist for testing, branching, calling, returning, if, and so forth. The EIA appears to have added some of the more interesting methods, such as call, return, and if, as an afterthought the standard just gives their name and method ID. The specification also doesn't bother to mention what the tokens null, minimum, maximum, default, bit-string, endoffile,...

In Conclusion

You might have thought that wiring the signal-conditioner board would be the most demanding task, but I found doing so merely time consuming. Attaching the sensors and mounting the board in the wood locker in the middle of a Connecticut December confirmed my addiction to home control. It will be a while before all the data is in, and no doubt Ken and I will have to have some discussions about having certain HCS math functions do some of the things I want to do. However, don't doubt for a minute...

Inertia

A body at rest tends to stay at rest, and one in motion tends to stay in motion. This law is extremely important when moving loads with a large mass. How fast does your automobile go from 0 to 60 MPH Not instantly No matter how hard you tromp on the gas, your vehicle takes,time to accelerate to cruising speed. The constant force of those horses under the hood pulling or pushing you continuously add together to move the large vehicu- lar mass. Coming to a stop is not instantaneous either, unless...

Info

Table 2- n a mere 16 bytes, you can raise the volume, mute the sound, turn on the surround sound, resefthe sharpness to a preferred level, and set the sharpness to a specified level on a hypothetical television sef. Table 2- n a mere 16 bytes, you can raise the volume, mute the sound, turn on the surround sound, resefthe sharpness to a preferred level, and set the sharpness to a specified level on a hypothetical television sef. method arguments, and variables is in the structure of the context...

Interface

'PROVIDES SOFTWARE CONTROL OF RELAYS J 'PROVIDES SOFTWARE CONTROL OF RELAYS J VR-16 RELAY INTERFACE I 89.9 5 'woSchannel relay output ports are provided for control ot pto 16 relays (expandable to 128 relays using EX-16 xpanslon cards). Each relay output port connects to a slay card or terminal block. A variety of relay cards and slays are stocked. Call for more Info. RS422 available distances to 4,000 feet). PS-4 port selector may be used control satellite AR-16 Interfaces, (up to 16.364...

Interpreting

To execute a CAL program, the interpreter repeatedly calls the parser, acting on each returned type. It makes note of any context or object changes. For method types, it uses the current context, current object, and method ID to decide which method to call. The method calls the parser to get any arguments it needs. When the method returns, the interpreter skips any method arguments by parsing until it encounters a nonargument type (see the top half of Table 1 ). The interpreter repeats this...

Interpreting The Patent

Certainly no one single patent involves the use of the RS-485 bus, but this example is the only one in which the author called out the text RS-485 precisely. Reading the abstract, you can see that the topic of this invention is actually a token-passing bus system. If you were to do a further search on the keywords token pass * (note, wildcard identifiers are permissible), you would find a large number of matches. Among these are also some patents referring to board games, ice chests, and coin...

Journal

FOUNDER EDITORIAL DIRECTOR Steve Ciarcia ENGINEERING STAFF Jeff Bachlochl & Ed Nisley CONTRIBUTING EDITORS John Dybowski & Russ Reiss STAFF RESEARCHERS Northeast John Dybowski Midwest Jon Elson & Tlm McDonough West Coast Frank Kuechmann CIRCULATION COORDINATOR Rose Mansella CIRCULATION ASSISTANT Barbara Maleski CIRCULATION CONSULTANT Gregory Spitzfaden CIRCUIT CELLAR INK, THE COMPUTER APPLICATIONS JOURNAL (ISSN0896-8985) Is published monthly by Circuit Cellar Incorporated. 4 Park...

Machine Time

This idea of Julian time seems right, and there is no reason why you can't extend this principal to obtain the linear reckoning needed, but you must go further to convert the date from the real-time clock to an entirely linear format. You can make this conversion easily using either a combination of lookup tables and arithmetic or just the tables alone. Select the approach that best suits your processor's capabilities. Figure 4 TheDSl387 clock module may be connected directly to the processor's...

Measuring The Effect Of Step Format On Torque

To make good use of the 5804's versatility, I wanted to experiment with the different wave formats to determine the torque differences between wave, two-phase, and halfstep drives. I chose a Seiko STP4296L-50 stepper motor (available from Digi-Key as part number STPl12) for my tests. The test setup includes a platform that holds the stepper's motor shaft parallel with the floor at the edge of the bench. Since I was dealing with torques in the range of gram-centimeters, I attached a pulley with...

Methods

The file met hod. c contains the CAL methods. Macros at the beginning and two functions at the end provide routines for getting, checking, and comparing various kinds of arguments. I implemented most of the methods. However, I had to guess what the EIA intended for many of them because of the sparse documentation. The methods turned out to be pretty simple, but there are a lot of them. A manufacturer would include only the methods needed. Remember that the connection between a method ID and a...

News

Huntsville Microsystems announces the release of its new LITE series of real-time emulators for the Motorola 68300 family. The units include HMI's powerful SourceGate debugger. provides full emulator control integrated with source- support for all major C and Ada compilers. SourceGate uses a high-speed serial port (115.2 kbps) to support communications, and a parallel port for code downloading. The emulators are configured with 256 KB of RAM and support mapping of all chip select signals with...

Nheads 0 0 0

03 OEM name and ver (8 chars) Ob bytes per sector Od sectors per cluster Oe reserved sectors 11 maximum root dir entries 13 total sectors on diskette 18 sectors track ( head) la number of heads lc number of hidden sectors 20 number of sectors if > 32 MB 2b volume label (11 chars) 33 file-system type (8 chars) 8 Digital channels (8ch. logic analyzer) 125MHz Single shot Bandwidth 4K samp les channe 1 (ana log & d ig ita 1 ) 8 Digital channels (8ch. logic analyzer) 125MHz Single shot...

Open System For Interconnecting Peripherals

Gigatec S.A. of Switzerland has introduced an innovative technology for connecting numerous peripherals to one controlling computer. The LISbus Asynch I O System is a cost-effective method of communicating with as many as 100 peripherals at distances up to 4,500 feet without expensive network hardware and software. LISbus establishes a hard-wire connection through analog switching elements with any single slave peripheral chosen at any time. The connection provides eight transmission lines and...

Parsing

A CAL parser gets the next byte from the CAL program by looking it up in the left column of the table, and it returns the specified return type and return value. Thus, 22 parses to a type of value7 and a value of 22. I'll write this statement as vahie7 22. The code F5 FF parses to value8 FF. To parse a context (F6) token, the parser calls itself recursively to get the next token. The token returned must be type value7 or valueS (value7 8 for short). The parser returns the type context and the...

Patent Talk

Have found the readers of the Computer Applications 'Journal to' be some of the most creative designers anywhere. However, even the most creative people can become stagnant, and seeing how someone else solved a problem can stimulate the flow of ideas. This creativity boost is one of the reasons why patents (and this magazine) exist. Beginning this month, I will be bringing you abstracts and other interesting tidbits related to actual patents issued by the United States Patent Office. Some will...

Pccompatible Embedded Control System

MJS Designs has introduced a new tool for embedded control using an IBM PC or compatible. The Total Control 2000 (TC2000) is a unique way for engineers to develop standard microcontroller functions and for experimenters to create the perfect electronic home. It incorporates the features of a learning tool, hardware developer, and programmer's kit. The TC2000 kit includes an ISA-compatible PC card that has standard I O features, such as 10-bit ADC, 16- bit pulse with modulators, edge detector...

Pdk51

The PDK51 is a fully integrated hardware, firmware, and software system designed to help you develop your products quickly and cost effectively. All you need to use the PDK51is an IBM-PC XT AT or compatible. We supply the rest. SIBtC-ll microcontroller board (8052AH-BASIC CPU) with IbK RAM BASIC interpreter source on disk SIBhC-ll hardware manual with schematic Monitor debugger ROM plus manual Monitor debugger hardcopy source listing Programming power supply adjustable from 4V to 2bV KCRMI1...

Phantoms

Phantom clocks, as the name implies, coexist in the same address space as other memory devices such as a PROM or a RAM. These serial devices often incorporate power monitoring and control circuits and backup power sources that can nonvolatize collocated static RAM chips. Parts like the Dallas DS 12 16 operate as a socket residing in a memory site on the printed circuit board into which a memory device is plugged. For the most part, these clocks remain disabled and stay out of the way while...

Pin 8

Figure 1-This circuitry converts the printer port into one input and one output byte. The inputs are pulled up by resistors on the I O card, while the outputs have (barely) enough drive for the LEDs. Note that the LEDs are ON when the outputs are HIGH, which is backwards from many LED drivers seen in these pages. The header provides convenient scope access, and will come in handy next month when I tackle performance issues. address 0000 7C00 and jumps to the first instruction. If that sounds as...

Quality Products Responsive Service Reliable Delivery

SOLID STATE DISK - 122* Vi Card 2 Disk Emulator EPROM. Flash and or SRAM 1 Meg Total, Bootable SOLID STATE DISK - 122* Vi Card 2 Disk Emulator EPROM. Flash and or SRAM 1 Meg Total, Bootable 2 Serial, 1 Parallel Port Up to 2 Flash Drives, 1 Meg Total Software Included, 2 Meg DRAM 40Mhz, IDE, FDC, SVGA IPar, 2Ser (232 422 485), Cache .Solid State Disk-2 drives to 2.5 (leg 2 Serial, 1 Parallel Port Up to 2 Flash Drives, 1 Meg Total Software Included, 2 Meg DRAM 40Mhz, IDE, FDC, SVGA IPar, 2Ser...

R

Table 2 There are six thermocouple types, each with its own characteristics. Most designers avoid thermocouples because using them has usually involved considerable circuitry. Table 2 There are six thermocouple types, each with its own characteristics. Most designers avoid thermocouples because using them has usually involved considerable circuitry. in 100 sections. Cost is 1 to 50 depending upon type and packaging. *Using thermocouples requires an actual or mathematically derived correction...

Real Time

As you know, many embedded designs incorporate real-time clocks. Often these clocks are present only in order to tell time. At times, the clock chip is used to display the date and time on a local display device or to timestamp data records before they are placed in memory for later processing. For these operations, the values dispensed by real-time clocks are just what you need. However, some activities suffer from the ambiguity inherent in the notation commonly used by real-time clocks. This...

Realtime Clock Chip Features Nonvolatile

Dallas Semiconductor has introduced a new series of timekeepers with real-time clock calendar and nonvolatile RAM functions accessible in a byte-wide format. The DS164x Timekeeping RAM series features memory densities in the range of 2-5 12 KB. Easily substitute the device packages, which adhere to JEDEC byte-wide pinouts, in ROM, EPROM, and EEPROM sockets providing R W nonvolatility with the addition of a real-time clock. The devices incorporate the real-time clock registers in the uppermost 8...

Rotary To Linear Motion

The rotary motion of stepper motors is often translated into linear motion for positioning systems and can be accomplished in several different ways. Line printers can use a rack and pinion to move a print head across the paper. Some floppy drives use a cylinder and band to move the read write head from track to track. Plotters might use a pulley and cord to position the plotting pen. NC drilling machines use gears and lead screws for linear positioning. Even line printers and fax machines use...

Serial Time

Dallas Semiconductor has a small serial clock that is inexpensive and stingy on the I O pins. Packaged in an eight-pin DIP, the DS1202 provides a real-time clock calendar and contains 24 bytes of static RAM. Three pins carry communications to the chip a reset input, a clock input, and a bidirectional data line. You provide a crystal, and if you want nonvolatile operation, a couple of low-dropout diodes and a backup power source. Access is fast for a serial device, because the minimum clock's...

Silicon Update

Silicon intelli-' gence permeates 'systems, designers making the tradeoff between hardware and software face more choices than ever. Traditionally organized design teams, in which hardware and software groups work separately, are subject to a disadvantage best described by that old saying, If the only tool you have is a hammer, everything looks like a nail. Each side may lobby that their way is the right way, both ignoring possibly more optimal firm (combined hardware and software) solutions....

Single Board Computer

Has optimum features for data aquisition and control. Professionally designed and built for tough applications with a 2 ear warrantee and a 30 day money back guarantee. programming sasnap in either multi-tasking Basic,Forth or ansi c. features NCLUDE , * 8 OPTICALLY COUPLED DIGITAL INPUTS * 8 HIGH DRIVE BUFFERED DIGITAL OUPUTS * 16 PROGRAMMABLE DIGITAL I O LINES * 16, THIRTEEN BIT ANALOG INPUTS * 2 OPTIONAL TWELVE BIT ANALOG OUTPUTS * 4 SERIAL RS232 485 SERIAL PORTS * Up TO 512K MEMORY plus...

Smart House Usage

SMART HOUSE is currently aimed at the new construction market with professional builders and installers the intended buyers. Equipment for retrofits is still being developed at this time. For more information on SMART HOUSE, contact SMART HOUSE L.P., 400 Prince Georges Blvd., Upper Marlboro, MD 20772, (301) 2496000. Brooke Stauffer is Technical Director, Regulatory Affairs for the Association of Home Appliance Manufacturers (AHAMj. He was previously Manager of Codes and Standards Development...

Software

Software for this article is available from the Circuit Cellar BBS and on Software On Disk for this issue. Please see the end of in this issue for downloading and ordering information. Ed Nisley is a Registered Professional Engineer and a member of the Computer Applications Journal's engineering staff. He specializes in finding innovative solutions to demanding technical problems.

Solid State

Proven Performance For OEM Military, Embedded Systems, Diskless High Performance PC's, CAD CAM, Industrial Control, Medical, POS, LAN's, etc. . High Capacity Models (PCF PCM) . Low Cost Models (FERO,E 2-SR Special OEM) Dual Mode Emulation Models (PCF, PCM 2, PCE 2) Autoboot Capabilities, all models MS DOS DR DOS E-Venix OS Support . NEW PCMCIA models (PCM, PCM 2) and accessories Industry Leader in Disk and Drive Emulation Products 418 W. County Rd. D . St. Paul, MN 55112 PR DOS is a trademark...

Source

Brooke and Mullin, Ray C SMART HOUSE Wiring, Delmar Publishers, 1992. Available for 21.95 (plus shipping) from Delmar Publishers at (800) 998-7498. Just published in November, this new book is the comprehensive guide to designing and installing the SMART HOUSE system for new homes. Three new cables, special wall outlets, and an integrated distribution system called the service center put all the electrical and electronic services together in one neat package. The SMART HOUSE system...

Sources

NW, Ste. 200 Washington, DC 20006 Canadian Automated Buildings Association (CABA) M-20, 1200 Montreal Rd. Ottawa, Ontario K1A OR6 (613) 990-7407 Fax (613) 954-5984 The Training Department 5755 SW Natchez Tualatin, OR 97062 (503) 692-8296 Parks Associates 53 10 Harvest Hill Rd. Suite 235, Lock Box 162 Dallas, TX 752305805 (214) 490-1113 Fax (214) 490-I 133 Residential Micro Systems 14713 Pleasant Hill Rd. Charlotte, NC 28278 (704) 588-2453 Intellon Corp. 5 150 West Highway 40 Ocala,...

Step Formats

The 5804 stepper motor translator driver chip supports three step formats wave, two-phase, and half-step sequences. The wave drive sequence energizes only one coil at a time. The sequence is either A-B-C-D-A or A-D-C-B-A, depending on the direction control bit. The wave drive power supply must provide current to only one winding at a time, making it less expensive. The rotor moves from one energized stator pole to the next. The torque produced is also small because it is proportional to the...

Superior02

R w a r d substate Fss) spreading q u e n c e Figure 2 The superiorOt state is made up of seven substates and lasts one unit symbol time. The superior02 state is identical but has the order of the substates reversed. Figure 2 The superiorOt state is made up of seven substates and lasts one unit symbol time. The superior02 state is identical but has the order of the substates reversed. Figure 3 I he data portion ot encoded by the duration of each work my way down to the actual modulation scheme...

System Architecture

The SMART HOUSE control communications subsystem is responsible for the coordination, operation, and management of house functions. Its two primary functions are controlling energy delivery to outlets and appliances, and providing pathways for appliances and system components to exchange messages and functional requests. It exchanges data and messages between appliances and the system controller or between two or more appliances, using the Core Language and the object-oriented SMART HOUSE...

Th Crcut CeIIar Project FHe VoIume

The Circuit Cellar Project File, Volume 1 has over 200 pages of new and expanded hands-on projects and tutorials. The Computer Applications Journal's editors have chosen a dozen of the top projects from the Circuit Cellar Design Contest, independent submissions, and top-response articles to make a book with something for every interest The Circuit Cellar Project File, Volume 1 has over 200 pages of new and expanded hands-on projects and tutorials. The Computer Applications Journal's editors...

The Beef

Where am I leading with this For a long time now I've been saying CEBus is right around the corner. Well, CEBus is finally here-at least the final specification is, anyway. About two years ago, the committee released the upper network layers and started releasing the physical layers as they were finalized. The last of the physical layers (RF) has been finished, and you can now purchase the complete specification. CEBus is now in such a form that companies can start designing it into their...

The Essence Of A Patent Abstract

So patent abstracts are available conveniently on CD-ROM, and knowing about them will increase the flow of my creative juices-what does an abstract look like, anyway To best illustrate the features of a patent abstract, I'll describe a simple search using APS. Say that I'm curious wnat patents exist regarding t'ne RS-485 serial bus protocol. I might simply enter into the APS search screen the search parameter RS-485 as is shown in Photo 1. In a couple of seconds (using a Hitachi CDR3600 350-ms...

The First Program

The canonical first program on any system displays a trivial message like C's Hello, world routine, but your '386SX doesn't have a display. Think small-your first 803 1 program probably blinked an LED, and that's the level you're at with this project. Unfortunately, a '386SX system board doesn't even have an LED Listing 1--The Diskette Boot Record holds the information needed to read the rest of the diskette. Assembler macros define the constants starting with N_ to create a boot record for...

The Lingo

The angular movement of a stepper motor is measured in degrees. The number of degrees the shaft rotates for each winding's phase change, or step, is its step angle. The most common step angles are between 1.8 and 18. The step accuracy is the difference between the theoretical and the actual step angle, which is generally 5 of the step angle and is nonaccumulative. A stepper that remains stationary while energized is exhibiting a resistance to change called holding torque. This torque is the...

The Ucn5804bunipolar

Four transistors and a bit of software are all that's necessary to drive a stepper motor's coils in the proper sequence, but it requires the processor's full attention. If your system has other things to attend to and you would like to keep everything simple, then use the single-chip approach. The UCN5804B from Allegro Microsystems has built-in sequencing logic for three types of step formats as well as direction control. Transistors are included to drive a unipolar motor up to 1.5 amperes from...

Thepausethatrefreshes

Often, an application requires only the simplest of displays like a two-digit O-99 counter. The ubiquitous seven-segment LED (which is actually eight-segments if you need a decimal point) can handily represent the digits 0 through 9 and other characters as well (within the limitations of its sparse matrix). approach is simply to allocate seven lines per display, driving each LED display segment as you would a discrete LED. In this case, the driver software is little more than a lookup table...

There Are No Easy Temperature Measurements

Before I elaborate on the ADIO connection to the HCS, I need to discuss getting temperatures converted into levels suitable for 0-5-volt computer systems. A great many people imagine that you simply take a two-wire probe and screw it on the ADC input or at the most you use an LM34 direct-voltage-output integrated sensor and everything is solved. As a matter of practicality I'd say possibly, but my experience suggests that only the other guy gets to do it simply As I start describing the process...

Thermocouples

Table 2 shows the six thermocouple types. Most designers avoid thermocouples because using them has usually involved considerable circuitry. The physical characteristics that produce temperature-sensitive outputs from thermocouples must also be compensated for elsewhere within the signal-conditioning circuitry. When two dissimilar metals are joined, a voltage differential proportional to the temperature is produced at that junction. If you know the types of metals, such as copper or Chromel,...

Time

The Circuit Cellar BBS 300 1200 2400 9600 14.4k bps 24 hours 7 days a week (203) 871-1988 Four incoming lines Vernon, Connecticut If you avoid calling the Circuit Cellar BBS because you fear longdistance phone bills, we've made some improvements that may ease that fear. First, we now have three V.32bis 14.4-kbps modems to make your connections f y. Ihese work with all the latest speed, data compression, and error correction protocols (V. 32, V.32bis, V.42, V.42bis,MNP5, etc.). Second, we now...

Tm

Micromint introduces its new Power Line Interface for X-10. PLIX is an 18-pin ASIC chip that automatically handles all the specialized X-10 timing and bit-shuffling between a computer and a TW523 power line module. Jt Complete inter ice between parallel port and T 523 or I'l.fi I 3 modulo JC Perform. - all X-10 transmit and receive lurnlions K Detect- AC power loss it Simple interface and timing operates even in interpreter BASIC JC Low power - onlv 1.8 m .> V PLIX chip and dala sheet 100...

Training

One of the first requirements when introducing anything new is basic user training. The standard won't go anywhere Figure 3 I he data portion ot encoded by the duration of each SUPERIOR82 SUPERIOR81 SUPERIOR91 SUPERIOR92 SUPERIOR82 SUPERIOR81 SUPERIOR91 SUPERIOR92 a typical data packet is transmitted by alternating between two different states. Symbols are state. 101011001000111. One bit of the PMF is XORed with each chip in a substate spreading sequence to cause all the bits in the sequence to...

True Rms Dmm With Rs232

> Includes RS232 to PC Cable and Data togging Software > Measures AC-DC V, A, Ohms, Freq. 846 SEVENTEENTH ST., INDUSTRIAL PARK PRAIRIE DU SAC, Wl 53578 TEL (608) 643-8599 AX (608) 643-6754 Sendcheck, MO, VISA, MASTERCARD, AMERICAN EXPRESS or P.O. Please include 8 forSffl

Ucc

Figure 2-The AC power line is often an excellent timebase in embedded applications because the optoisolated interface is so simple. Figure 2-The AC power line is often an excellent timebase in embedded applications because the optoisolated interface is so simple. source, the output voltage remains above 3 volts throughout the lifetime of the cell. However, load curves involving such light currents are seldom plotted due to the long times involved in taking these capacity measurements. Because...

Upcoming Events

In the next column (next month ), I'll describe how to persuade Dave Dunfield's 8086 version of the Micro-C compiler to produce programs for the floppy drive loader, then I'll take a look at low-level hardware performance. After all, you need to know just how fast this beast will run before you decide how much you can do with it. After that I'll get into the first real hardware project-a firmware development card with some EPROM, battery-backed write-protected static RAM, a watchdog timer power...

Userprogrammable Risc Microcontroller Features

Microchip Technology has introduced an advanced, low-cost, 8-bit RISC microcontroller with on-chip A D conversion and an upgraded CPU core. The features internal and external interrupt sources, an expanded stack memory, and 14-bit-wide instructions. The chip maintains the advantages of user programmability while adding a four-channel, 8-bit ADC with a conversion rate of 20 ps per channel. The RISC instruction set consists of 35 instructions, each of which executes in one 200-ns instruction...

Using The Interpreter

A program that uses the interpreter must have a method table array, a context list, and a variable list (see Listing 2). To set up the interpreter, load cal MethodTabl e with the address of the method table, load c a 1 Met hod T a b 1 e Len with the number of entries in the method table, load cal Context with the address of the context list, and load calVarLi St. with the address of the variable list. To interpret CAL code, plug c a 1 Ret with the address of the CAL code and call c a 1 E v a 1....

Using The Lm34 Is A Matter Of Scaling

I can monitor the other four temperatures in a variety of ways, Looking for the kernel that makes application debugging both quicker and easier Look to KADAK for the AMX' real-time multitasking kernel featurmg the Night' Debug Tool. AMX and InSight cooperate with such industry standard source level debuggers as GxleViewJ FreeForm, Turbo Debugger and XRAYr But that's just the start. With Insight, a single keystroke will give you a full screen view of all your tasks, timers, mailboxes, messages,...

Videoframe Grabbers

Image Drive Ram Disk Emulation course these numbers include total patents on all subjects, not just on RS-485. Note also that those 58 thousand patents were issued to Japan in just a little over two and a half years Generally though, your initial interest is in the abstract itself. The inventor or his patent attorney) writes the abstract, representing the assignee's summary of the patent's description. If what you see looks worthwhile, you should then go on to read the actual body of the...

West Coast

Circuit Cellar BBS 24Hrs. 300112001240019600114 4kbps, 8 bits, nopanty, 1 stop bit,(203)871-1988 2400 9600 bps Courier HST. (203) 871-0549 All programs and schematicsinCrrcu f Cellar INKbwe been carefully reviewed to ensure their performance is In accordance with the specifications described, and programs are posted on the Circuit Cellar BBS for electronic transfer by subscribers. Circuit Cellar INK makes no warranties and assumes no responsibility or liability of any kind for errors In these...

V

Brooke Stauffer Switched-On CEBUS A CAL Interpreter Add Some Temperature Sensors to the HCS II by Steve Ciarcia Editor's INK Ken Davidson Increasing the Bandwidth New Product News edited by Harv Weiner Firmware Furnace Ed Nisley Blindsided by Technology The '386SX Embedded Firmware Project Simple Steps for Easy Positioning Controlling Smart LEDs The Hard Way, the Soft Way, Embedded Techniques John Dybowski Embedded Timepieces Patent Talk Russ Reiss Let Me Explain...

Processor

80C52-BASIC, 8-bit CMOS microcomputer -lumper-selectable conversion to 80C31 80C32 functionality 8Kbytes ROM (full BASIC Interpreter) 256 bytes RAM three 16-bit counter timers 32I O lines 1 l MHz system clock up to four 6264 (8Kx8) static RAM either an 8K 2764 or 16K 27126 EPROM B C C 5 2 BASIC Controller Board witft 8K RAM BCC 5 2C Lower-power all-CMOS version of the BCC52 BCC 521 Full industrial temperature range BCC 52CX CMOS. Expanded BCC6 W 32K RiM -console I O RS-232 serial port line...

Firmware Furnace

Blindsided by Technology The '386SX Embedded Firmware Project Having long ago pushed the little 8031 to its limits, Ed has set his sights on a new development platform for future projects. While some may think his choice is overkill, you'll soon agree with his reasoning. uppose your project needs a high-performance 'CPU, lots of DRAM, comprehensive interrupt and DMA support, a real-time clock, nonvolatile configuration RAM, serial and parallel ports, and a megabyte-per-second I O bus. Quick How...

Day Moneyback Guarantee

RHOMBUS DESIGNS, INC 5 Wood lawn Green, Suite 220 Charlotte, NC 28217 For instance, you may have to permit activities such as entry onto the premises around certain time, say perhaps a period of 15 minutes around 5 00 P.M. Things get a little tricky when the time is centered around 00 00. Although you can code around these special cases, doing so makes for a lot of special processing. Generally, making things as simple as possible is best, but when dealing with any nontrivial matters, there's a...