

Quadram MicroFazer Data Buffer. (evaluation) David H. Ahl.

Quadram MicroFazer Data Buffer

The Quadram MicroFazer is a self-contained data buffer that connects between a computer and a printer. The MicroFazer receives data from the computer at a high speed (up to 4000 characters per second). It stores these data in its own memory, then feeds the data to the printer as the printer can handle them. This buffering action means that you need not tie up your computer while printing a lengthy document.

Time Saving

Does the MicroFazer really save time? You bet. An article written in-house for Creative Computing is either transcribed by a secratary from a dictation tape on a word processor or written directly on one. This first draft is then corrected by the author and printed out a second time. It is then routed around to the other editors for comments, changes, and corrections. Following that process, it is printed out again.

One article I wrote recently was 4178 words long. A double-spaced printed version ran 17 pages and took 11 minutes and 40 seconds to print (about 40 seconds per page) on an Epson MX-80 printer. Do the arithmetic and you will find that this is a print speed of about 44 characters per second, slightly over one-half of the rated 80 cps speed of the Epson. We found this differential true across the board in our printer evaluations. Hence, speeding up the printing process may be more worthwhile than published figures might lead you to believe.

In any event, the 4178-word document was transferred to the MicroFazer in about 15 seconds. The computer was then no longer occupied with the printing process and was free to do something else. On the three printouts of this article, the MicroFazer saved 35 minutes of computer time, a significant saving indeed.

The computer time necessary for printing with and without MicroFazer is in a ratio of about 46:1 with Epson and other dot matrix printers in the 80 cps speed range. The savings are proportionately greater with slower printers and less with faster ones.

Hardware and Installation

The MicroFazer uses a custom LSI chip and up to eight 64K bit RAM memory chips on a single board. It is possible to purchase the MicroFazer with just one chip installed (8K bytes) and then upgrade it with more memory later on. Quadram supplies versions of the MicroFazer with 8K, 16K, 32K, 48K, and 64K. You should choose a version with enough memory to handle the longest documents you normally write.

MicroFazer may be plugged directly into Centronics-compatible printers. You simply unplug the cable connected to the printer, plug the MicroFazer cable into the printer, and plug the computer cable into the MicroFazer.

If the printer you are using is not Centronics-compatible or does not use a G-520 36-pin connector, you will have to make or purchase modified cables. A block diagram of the MicroFazer including all connector pin designations is in the manual.

Power is supplied to the MicroFazer either directly from the printer or from an external 9v power supply. Some printers have power available on pin 18 while others, including the Epson series, do not.

The manual includes a simple modification which allows Epson MX series printers to get power for the MicroFazer. You must remove the bottom cover of the printer, remove the top printed circuit board, and run a jumper from one of the resistor pins to connector pin 18. It is a simple modification but, unfortunately, voids the Epson warranty. If you don't want to do this you can, of course, use the external supply.

An external power supply is not furnished by Quadram but one can be purchased in most electronic outlets for $5.00 or $6.00.

The MicroFazer comes in two case styles, free-standing and snap-on.

The snap-on unit measures a compact 3.5 X 7 X 1 while the free-standing one is slightly larger, 5.5 X 8 X 2 . The snap-on unit bolts to the back of the printer. It has just one external control, a reset button. It also has a red LED which indicates whether it is ready to receive data. An internal slide switch is used to choose between internal and external power.

The free-standing unit also has a reset button, ready indicator, and external power supply switch. In addition, it has an LED which indicates an error condition (cable not plugged in, printer not ready, etc.). A second pushbutton switch, labeled "Copy' is used to repeat the print operation with the data in the MicroFazer buffer. When this has been pressed, a red "Copy' LED is illuminated.

MicroFazer is available in three configurations, parallel in/parallel out, serial in/parallel out, and serial in/serial out.

If you are doing a really heavy volume of printing, two or more MicroFazers can be connected end to end to obtain increased buffering (128K, 192K, or more).

Another related product by Quadram is InterFazer which is described in the manual as "an intelligent controller/buffer that allows up to eight computers to be connected to one or two printers. Computers can be connected either through serial or parallel input ports and the printers can be serial or parallel. Inputs and outputs do not have match.'

Simple Operation

Once installed, the MicroFazer is invisible to the user. Upon powering up your system, you simply turn on the computer, printer, and MicroFazer. If everything is plugged into a switch-type power strip, one switch can bring up the whole system. The "ready' indicators on the printer and MicroFazer should both be on. If they are not, pressing the reset button on MicroFazer should bring everything to a ready state.

During printing, the MicroFazer reset button will clear the buffer and halt the print process.

As long as the ready LED is illuminated, you can send data to the MicroFazer. For example, if you are printing a long document and finish editing a short one, you can send it to the MicroFazer and go on to something else. Just be sure the second document starts with a printer form feed.


The MicroFazer saves a significant amount of computer time when printing long documents. With a slow daisy wheel printer (40 cps and under), the computer will be tied up for printing less than 1% of the time it would be without the MicroFazer. With a medium speed printer (80 cps range), the time saving is about 1 to 46, while with a higher speed printer (200 cps) the saving is still a significant 1 to 20.

MicroFazer is easy to install on most printers with parallel Centronics-type connectors or serial DB-25 type connectors. In normal operation, MicroFazer is invisible to the user.

The price of a parallel/parallel 8K freestanding MicroFazer is $169; the snap-on unit is $10 less. Both 64K units cost the same, $299. MicroFazer is available in many computer stores or directly from the manufacturer, Quadram Corp., 4357 Park Dr., Norcross, GA 30093. (404) 923-6666.

Products: Quadram Microfazer (Input-output device)