IBM 4400 manual Novram, Ocr

Appendix D

NOVRAM	Acronym of NonVolatile Random-Access Memory. See
	also nonvolatile memory.

	O
OCR	Optical Character Recognition is the process by which
	a machine reads characters printed in a special
	standardized font. Data are read by a photoelectric
	optical scanner and recorded on magnetic tape or disk.
	OCR-A and OCR-B are two widely used fonts.

	P
Parity (check)	Parity checking is the addition of non-data bits to data,
	resulting in the number of 1 bits being either always
	even or always odd. Parity is used to detect
	transmission errors. Parity represents the value in the
	check digit of the received or transmitted data.
Parsing	Parsing is the process of separating a programming
	statement into basic units that can be translated into
	machine instructions. A printer can recover from an
	erroneous code sequence by performing as much of
	the function as possible or, parsing the valid parameter
	from the invalid.
PI	Paper instruction: A signal from the host with the same
	timing and polarity as the data lines.
Pin configuration	Establishes the physical attachment and protocol
	conversion connections for the host interface.
Pitch	The number of text characters printed per horizontal
	inch. Specified in characters per inch or cpi.
Pixel	Acronym of picture element or picture cell. The smallest
	displayable picture element on a video monitor or
	printable unit in a printer.
Point	A unit of measure in printing and typography, used to
	specify type sizes, heights of font characters, etc. There
	are 72 points in a vertical inch; thus, one point equals 1/
	72 inch, or approximately 0.0138 inch. Examples: This is 6
	point type. This is 10 point type. This is 16 point
	type.
Print Mode	The horizontal and vertical dot density at which the
	characters are printed.

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