## Word

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Fig. 2. Large computer, typical word. The computer word is broken down into data "bytes" as explained in the text. The bytes are further broken into their respective data ''bits." The "home brew" computer is 'byte oriented" to the extent that registers are 8-bits (one byte, or character, long).

The Hewlett Packard Computing counter performs sophisticated anaiysis and doubles as a desk top calculator v/ith the counter input serving as one of the variables.

from discrete components. Keep in mind that, unless you have the parts on hand, building each flip-flop, etc. will increase the cost of the project, and using discrete components will definitely increase package size.

### Circuit Details

Now let's look at the individual circuits of the computer and see if we can point out any other construction problems. When you begin to understand how the circuits within the computer function, you can more fully understand the overall operation of the machine. First, we will give a basic description of the circuits, then go into the details.

Input/Output

The input/output circuits (I/O) carry the data signals to and from the computer and the peripheral device. In most ham shacks, the peripheral will be the shack's teletype machine. The input/output circuits must provide buffering for the data signals to and from the computer. To buffer data, you must simply store enough of the data to allow ihe computer to take data when it is ready. If the data signals entered the computer before the computer needed the data, the result would be a very confused computer and an even more confused operator.

In order to buffer, the input/output circuits will have to store at least one complete teletype character. In fact just one TTY character would he called a "byte" (pronounced bit) in computer language, because the byte is the lowest number of data bits capable of storing a complete character. A data word would be a group of bytes just

For the most powerful antennas under the sun

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