|
The Automatic Proofreader
The Automatic Proofreader is a series of checksum utilities published by COMPUTE! Publications for its ''COMPUTE!'' and ''COMPUTE!'s Gazette'' magazines, and various books. These programs are designed to allow home computer users to easily detect errors on BASIC type-in programs, and work by displaying a hash value for each line entered that can be compared against the reference value printed in the magazine. Initially published for use with the Commodore 64 and VIC-20 in 1983, the Proofreader was later made available for the Atari 8-bit family, Apple II family, and IBM PC/PCjr as well. The line-by-line "real-time" feedback feature was something of a novelty at the time and represented a significant improvement over earlier checksum utilities, which were typically run only after a user program had been entered and, due to quite simplistic checksum algorithms, had trouble catching errors like transposed characters. Commodore versions The Automatic Proofreader was first introduced ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Checksum
A checksum is a small-sized block of data derived from another block of digital data for the purpose of detecting errors that may have been introduced during its transmission or storage. By themselves, checksums are often used to verify data integrity but are not relied upon to verify data authenticity. The procedure which generates this checksum is called a checksum function or checksum algorithm. Depending on its design goals, a good checksum algorithm usually outputs a significantly different value, even for small changes made to the input. This is especially true of cryptographic hash functions, which may be used to detect many data corruption errors and verify overall data integrity; if the computed checksum for the current data input matches the stored value of a previously computed checksum, there is a very high probability the data has not been accidentally altered or corrupted. Checksum functions are related to hash functions, fingerprints, randomization func ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Datassette
The third, most common version of the 1530 C2N Datassette The Commodore 1530 (C2N) Datasette, later also Datassette (a portmanteau of ''data'' and ''cassette''), is Commodore's dedicated magnetic tape data storage device. Using compact cassettes as the storage medium, it provides inexpensive storage to Commodore's 8-bit home/personal computers, notably the PET, VIC-20, and C64. A physically similar model, Commodore 1531, was made for the Commodore 16 and Plus/4 series computers. Features Typical compact cassette interfaces of the late 1970s use a small controller in the computer to convert digital data to and from analog tones. The interface is then connected to the cassette deck using normal audio cables like RCA jacks or 3.5mm phone jacks. This sort of system was used on the Apple II and TRS-80 Color Computer, as well as many S-100 bus systems, and allow them to be used with any cassette player with suitable connections. left, The Datasette loading process In the Da ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atari 8-bit Family Software
Many pieces of software were available for the Atari 8-bit family of home computers (the 400/800, XL, and XE series). Software was sold both by Atari, Inc. (then Atari Corporation starting in mid-1984) and third parties. Atari also distributed software through the Atari Program Exchange from 1981 to 1984. After APX folded, many titles were picked up by Antic Software. Programming languages Assembly language Atari, Inc. published two assemblers. The Atari Assembler Editor cartridge is a friendlier, integrated development environment using line numbers for editing source code similar to Atari BASIC. The professionally targeted Atari Macro Assembler shipped at a higher price on a copy protected disk without editor or debugger. Third-party assemblers include SynAssembler from Synapse Software and MAE (Macro Assembler Editor) from Eastern House. Optimized Systems Software published an enhanced disk-based assembler mimicking the structure of Atari's Assembler Editor as EASMD (Edit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apple II Software
An apple is an edible fruit produced by an apple tree (''Malus domestica''). Apple trees are cultivated worldwide and are the most widely grown species in the genus ''Malus''. The tree originated in Central Asia, where its wild ancestor, '' Malus sieversii'', is still found today. Apples have been grown for thousands of years in Asia and Europe and were brought to North America by European colonists. Apples have religious and mythological significance in many cultures, including Norse, Greek, and European Christian tradition. Apples grown from seed tend to be very different from those of their parents, and the resultant fruit frequently lacks desired characteristics. Generally, apple cultivars are propagated by clonal grafting onto rootstocks. Apple trees grown without rootstocks tend to be larger and much slower to fruit after planting. Rootstocks are used to control the speed of growth and the size of the resulting tree, allowing for easier harvesting. There are more t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disk Magazine
A disk magazine, colloquially known as a diskmag or diskzine, is a magazine that is distributed in electronic form to be read using computers. These had some popularity in the 1980s and 1990s as periodicals distributed on floppy disk, hence their name. The rise of the Internet in the late 1990s caused them to be superseded almost entirely by online publications, which are sometimes still called "diskmags" despite the lack of physical disks. Defining characteristics A unique and defining characteristic about a diskmag in contrast to a typical ASCII "zine" or "t-file" (or even "g-file") is that a diskmag usually comes housed as an executable program file that will only run on a specific hardware platform. A diskmag tends to have an aesthetically appealing and custom graphical user interface (or even interfaces), background music and other features that take advantage of the hardware platform the diskmag was coded for. Diskmags have been written for many platforms, ranging ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Random Access Memory
Random-access memory (RAM; ) is a form of computer memory that can be read and changed in any order, typically used to store working data and machine code. A random-access memory device allows data items to be read or written in almost the same amount of time irrespective of the physical location of data inside the memory, in contrast with other direct-access data storage media (such as hard disks, CD-RWs, DVD-RWs and the older magnetic tapes and drum memory), where the time required to read and write data items varies significantly depending on their physical locations on the recording medium, due to mechanical limitations such as media rotation speeds and arm movement. RAM contains multiplexing and demultiplexing circuitry, to connect the data lines to the addressed storage for reading or writing the entry. Usually more than one bit of storage is accessed by the same address, and RAM devices often have multiple data lines and are said to be "8-bit" or "16-bit", etc. devices ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore 128
The Commodore 128, also known as the C128, C-128, C= 128,The "C=" represents the graphical part of the logo. is the last 8-bit home computer that was commercially released by Commodore Business Machines (CBM). Introduced in January 1985 at the CES in Las Vegas, it appeared three years after its predecessor, the bestselling computer in the 80s Commodore 64. The C128 is a significantly expanded successor to the C64, with nearly full compatibility. The newer machine has 128 KB of RAM in two 64 KB banks, and an 80-column color video output. It has a redesigned case and keyboard. Also included is a Zilog Z80 CPU which allows the C128 to run CP/M, as an alternative to the usual Commodore BASIC environment. The presence of the Z80 and the huge CP/M software library it brings, coupled with the C64's software library, gave the C128 one of the broadest ranges of available software among its competitors. The primary hardware designer of the C128 was Bil Herd, who had wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore Plus/4
The Commodore Plus/4 is a home computer released by Commodore International in 1984. The "Plus/4" name refers to the four-application ROM resident office suite (word processor, spreadsheet, database, and graphing); it was billed as "the productivity computer with software built-in." Internally, the Plus/4 shared the same basic architecture as the lower-end Commodore 16 and 116 models, and was able to use software and peripherals designed for them. The Plus/4 was incompatible with the Commodore 64's software and some of its hardware. Although the Commodore 64 was more established, the Plus/4 was aimed at the more business oriented part of the personal computer market. History In the early 1980s, Commodore found itself engaged in a price war in the home computer market. Companies like Texas Instruments and Timex Group USA, Timex Corporation were releasing computers that undercut the price of Commodore's Commodore PET, PET line. Commodore's MOS Technology division had design ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore 16
The Commodore 16 is a home computer made by Commodore International with a 6502-compatible 7501 or 8501 CPU, released in 1984 and intended to be an entry-level computer to replace the VIC-20. A cost-reduced version, the Commodore 116, was mostly sold in Europe. The C16 and C116 belong to the same family as the higher-end Plus/4 and are internally very similar to it (albeit with less RAM – 16 KB rather than 64 KB – and lacking the Plus/4's user port and Three plus one software). Software is generally compatible among all three provided it can fit within the C16's smaller RAM and does not utilize the user port on the Plus/4. While the C16 was a failure on the US market, it enjoyed some success in certain European countries and Mexico. Intention The C16 was intended to compete with other sub-$100 computers from Timex Corporation, Mattel, and Texas Instruments (TI). Timex's and Mattel's computers were less expensive than the VIC-20, and although the VIC-20 o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
8-bit
In computer architecture, 8-bit integers or other data units are those that are 8 bits wide (1 octet). Also, 8-bit central processing unit (CPU) and arithmetic logic unit (ALU) architectures are those that are based on registers or data buses of that size. Memory addresses (and thus address buses) for 8-bit CPUs are generally larger than 8-bit, usually 16-bit. 8-bit microcomputers are microcomputers that use 8-bit microprocessors. The term '8-bit' is also applied to the character sets that could be used on computers with 8-bit bytes, the best known being various forms of extended ASCII, including the ISO/IEC 8859 series of national character sets especially Latin 1 for English and Western European languages. The IBM System/360 introduced byte-addressable memory with 8-bit bytes, as opposed to bit-addressable or decimal digit-addressable or word-addressable memory, although its general-purpose registers were 32 bits wide, and addresses were contained in the lower 24 bits of thos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whitespace (computer Science)
In computer programming, whitespace is any character or series of characters that represent horizontal or vertical space in typography. When rendered, a whitespace character does not correspond to a visible mark, but typically does occupy an area on a page. For example, the common whitespace symbol (also ASCII 32) represents a blank space punctuation character in text, used as a word divider in Western scripts. Overview With many keyboard layouts, a whitespace character may be entered by pressing . Horizontal whitespace may also be entered on many keyboards with the key, although the length of the space may vary. Vertical whitespace may be input by typing , which creates a 'newline' code sequence in most programs. On older keyboards, this key may instead be labeled , a holdover from typewriter keyboards' carriage return keys, which generated an electromechanical return to the left stop (Unicode character ) and a move to the next line (). Many early computer games used whitesp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
