Pablo Picasso, Portrait of Daniel-Henry Kahnweiler, Art Institute of Chicago An important aspect of modernism is how it relates to tradition through its adoption of techniques like reprise, incorporation, rewriting, recapitulation, revision and parody in new forms.
Sample source to encode a buffer address in a data stream. Since only six bits of each byte are involved in carrying significant information, it follows that these bytes can have 64 different values.
Figure 2 contains an example of assembler code to convert a binary location into address format. Note that they all correspond to EBCDIC displayable characters, as shown in the comments to the right of the hexadecimal.
Note also that the x'40' bit is on for each byte while the x'80' bit can be set on or off so that the whole byte corresponds to a convenient EBCDIC character.
The x'80' bit functions as a " parity bit". But why is it necessary that control codes consist of displayable characters? The answer is simple. The only devices that are character set dependent are those which produce a physical representation of a character for interpretation by another machine such as a card reader or a human being.
When a card punch remember them? When a card reader reads a card column with no holes punched it may send a x'40' down the line, but a card reader on a different system may send a x'20' instead.
Humans may regard a card column without holes as representing a blank or space, but what is the bit pattern of such a character? In other character sets it is probably something else. EBCDIC consists of different characters with x'00' to x'3F' and x'FF' being designated undisplayable control codes and x'40' to x'FE' being designated displayable character code points.
Actually, x'00', known as the "null" character, is displayable. With NULLS ON, trailing blanks are translated to nulls thus leaving room for data to be inserted with the use of the "insert mode" key.
If an input field on the screen has no null characters then no characters can be supplied in insert mode in that field. It is a relatively simple matter to map fixed control codes from one character set to another.
However, a problem arises when translating random control codes. If two character sets have the same number of characters then it may be possible to have a one-to-one reversible translation algorithm, but because ASCII only had different characters unambiguous translation of random bit patterns is impossible.
With no translation any character text remains unintelligible, whereas with translation the numeric data is rendered useless. The solution is to ensure that all variable control codes are made up of displayable characters which exist in both character sets.
With this method it becomes a straight forward matter to determine the original bit pattern from the resultant ASCII character string.
Consider the data stream for "repeat asterisks to location 84". Even though the screen buffer location of 84 is no longer directly encoded in the bit pattern of the order sequence, the terminal controller can decode the exact location specified.
This "send six meaningful bits per byte" solution is used not only for numeric control data but also for bit-encoded control bytes such as the WCC write control character and the attribute byte following an SF order.
The first two bits of these bytes are used to ensure an appropriate symbol, as listed in TABLE from figure 2, is formed with the first bit fulfilling the " parity bit" function and the second bit always being a one 1.
May Update - Thanks to Tom Armstrong. I am now informed that the real reason for the complex addressing scheme is because of support for remote screens via controllers.
BSC was an inherently non-transparent line protocol. Code points in the x'00' to x'3F' range were reserved for control characters for both BSC and start-stop terminals like the The last block in the chain would end with an ETX x'03'.
This also required additional programming support to turn it on and off. The designers of the system therefore faced a dilemma. Or, alternatively the datastream would have to be different for local s vs remote s.
The designers wisely made the decision to use a common datastream that did not demand the transparency feature by not using any character below x'40'. Hence we ended up with the buffer and order addressing scheme that looks a little crazy to some people who do not understand why it was required for remote s.
Another solution to the lack of binary transparency in BSC protocol was to take each byte and convert it into two bytes for transmission ie x'FF' becomes x'4F7F'. This was the technique used for the IBM terminal, but doubling the transmission time on slow bps lines was never an attractive proposition.Characteristics of Modernity Characteristics of Modernity Overview.
to argue that one of the defining characteristics of the modern era was the tendency toward specialization and. The Spiritual Competency Resource Center provides access to online resources that enhance the cultural sensitivity of mental health professionals.
Spirituality is now accepted as an important component of cultural competence for mental health professionals. These resources include online courses, audio-visual resources, articles, and live workshops. Figure 3. Buffer sizes of various screens.
Most applications assume the minimum screen size is that of the Model-2, the most popular, or at least populous, of the screen sizes widely available. Defining Characteristics of Modernity There have been numerous attempts, particularly in the field of sociology, to understand what modernity is.
A wide variety of terms are used to describe the society, social life, driving force, symptomatic mentality, or some other defining aspects of modernity. New Criticism. A literary movement that started in the late s and s and originated in reaction to traditional criticism that new critics saw as largely concerned with matters extraneous to the text, e.g., with the biography or psychology of the author or the work's relationship to literary history.
An analysis of the history of technology shows that technological change is exponential, contrary to the common-sense “intuitive linear” view.