Glossary - Omron SYSMAC C200H-ASC02 Operation Manual

Accumulator Register
ASCII Unit Program
Backplane
base address
baud rate
binary
bit
boot program
byte
communication port
data section
data transfer routine
data word
device control codes

Glossary

The arithmetic hardware register of the microprocessor.
The BASIC program that runs the ASCII Unit and communicates with the PC
program.
A rack of hardware slots sharing a common bus line to which the CPU and all
of its I/O Units are connected.
The first address of a block of memory or data. When a block of data is to be
transferred with one of the I/O commands, the base address must be speci-
fied.
The speed at which data is transferred during I/O operations. The baud rate
for the two ports is set with the right-side DIP switch. The standard baud
rates are 300, 1200, 2400, 4800, 9600, and 19,200.
The number system that all computers are based on. A binary digit can have
only two values, zero and one. The octal and hexadecimal number systems
are based on binary digits.
The smallest piece of information that can be represented on a computer. A
bit has the value of either zero or one. A bit is one binary digit.
The BASIC program that is automatically loaded into the ASCII Unit RAM
upon power up or reset.
A group of eight bits that is regarded as one unit.
A connector through which external peripheral devices can communicate
with a host computer or microprocessor. The ASCII Unit has two communica-
tion ports used to connect to a personal computer, printer, or other I/O de-
vices.
A special PC memory area that is assigned to each individual ASCII Unit.
The ASCII Unit uses the data section for reading and writing data to the PC
as well as for communicating status information.
The PC requires a dedicated data transfer routine incorporated into its pro-
gram in order to communicate with the ASCII Unit. A data transfer routine is
not necessary when the memory area designator parameter is used with the
PC READ and PC WRITE statements.
PC data is organized into units called words. Each word contains 16 bits and
has a unique address in the PC memory. When transferring a block of data
between the PC and the ASCII Unit, it is necessary to specify the address of
the first data word in the block as well as the number of data words to be
transferred. Throughout this manual the terms word and data word are used
interchangeably.
Keyboard strokes entered with the control key depressed that send control
messages to peripheral devices such as a terminal display or a printer. For
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