Since I have no en- gineering specs yet on these devices, I can ‘t say how accurate the plotter would be, but it would certainly drawl See figure 2. The data is blocked byte by byte, or not at all. I regard this method as less than satisfactory and suggest that there are better ways. Therefore, with the advent of quality low cost tape transports and speed tolerant one track codes, it is wisest to stick with single track recording. POLY 88 hardware provides many additional features that programmers have come to expect, such as vectored interrupt and real time clock. This code, however, has poor utilization of avail- able tape. The tilt causes a skew between otherwise perfectly manufactured gaps. Call routines give access to these from your software.

Buy only what you need now. Cartridge measures 4″ by 6″. The transition after that is the clock pulse for the next cell; it resets the counter and clocks out the contents of a flip flop which rec ords the possible transition of the BORROW output of the counter – then the process starts over. All of the transport functions, play, stop, rewind and fast forward, should be available on command by the computer. Multiple sounds can be generated with additional boards. But, you do need an interface to use the 2SI0 R with your own audio cassette. Lets you do more sophisti- cated work that might not otherwise be practical with a microcomputer. Each time a change is made to the tape, the directory copy in memory is updated and a copy of it is written back to the tape.

It will be shipped automatically. When the memory buffer finally empties, the read only memory is disabled and blanks the output for the rest of the print cycle. The user must supply some kind of flat panel with cutouts for the cassette tray, the eject lever and the index counter. Totally unrelated to our bar code representation for data, but nevertheless interesting, is this letter from C R Conkiing Jr, and his accompanying sample.


Also very annoying is the rather high price markup on the hardware by the time it reaches Australia. I must say, however, that it is in grade 2 Braille which uses contractions, as in speed writing.

These transports have usually been available to the original equipment manufacturer OEMbut the various manufacturers have indicated that they will sell to individuals serid groups. Took several years to develop.


The index register must be loaded with the starting address of the MP L parallel interface board olivethi the printer. Its arrival switches the mode of the counter into down counting. As a result, the field of personal computing as it is now known essentially centers around the building, testing and troubleshooting of computer kits.

See it at your local computer store. We held onto the letter until it was possible to announce an arrangement which should help promote and build an indigenous small computer industry in Australia: The three olivettk are referred to as fixed speed, variable speed, and Super Deck; their performance is tabu- lated in table 2.

A Review of Photo I: The line width control should then be adjusted for symmetrical margins. The learning may not be obvious as you are constructing the kit, but it is there and sooner or mofelo you will realize it.

That’s the Sol plan. As can be seen in the diagram, the printer motor is triac controlled, taking its on and off states from the position of the printer head on the page.

URANOS Installation

The circuitry, however, is very complex. The output PE data is generated polarity for the next data time, an additional transition can occur if needed at “phase time.


R5C Host Controller”. Again, a mismatch indicates an error has occurred somewhere along the line. End of tape and cassette sensing switches are extra. More sophisti- cated techniques which have great tolerance for tape speed variation and noise involve tracking oscillators or phase locked loops.

Data Formatting and Applications Once a means of recording and recovering data on cassette tape is secured, some decisions must be made on the formatting or layout of data on the tape.

Crystal controlled oscillator provides the clock signal for the processor and is divided down by the MC 1 to provide the various Baud rate outputs for the interface circuits. A graph portraying the approxi- mate relationship between the length of data blocks, assuming they are all the same fixed length, and the total data capacity of a C cassette is presented in figure 7.

The OSI Challenger is the only completely- assembled, ultra-high-performance, fully-expandable mainframe computer that does this much for this little. The lamp used is a 5 V,hour rated lamp.

Don’t run into roaming stars that can damage your ship.

Now there is no oluvetti for not building that robot you were thinking about. Bloom ington Michigan Rd. Put versatility and music into your computer today. Four kinds of cassette seire options are available using up to four micro switches to sense the cassette in place, record tab A and tab B and side A.

This diagram shows the concept of how to build a plotting bed based upon two model aircraft servo mechanisms.