WAGO I/O-SYSTEM 750 Manual page 208

208 Glossary
Opcode
For this I/O module: "Opcode" is the abbreviated form of "operation code". The
opcode is part of a Mailbox command (1 byte in length). The complete command
is formed by the opcode along with its arguments.
P
PI
(Process Image)
The process image (PI) is an area of the memory in which the process data for and
from modules/couplers/controllers is stored. The allocation and meaning of the
process data are module-/fieldbus-specific.
PIO
(Process Image of the Outputs/Output data)
Output process image
PII
(Process Image of the Inputs/Inputs Data)
Input process image
Packet
For this I/O module: A data/wireless packet consists of user data and header data
that are transmitted together.
Parameter channel
A parameter channel is an interface for parameterization of an I/O module. It is an
acyclic communication channel between the application and I/O module with 2
bytes of protocol information and 2 bytes of data (255 addressable data sets).
Parity
A parity bit is a simple check bit in a data word. The parity check is employed to
detect erroneously transmitted data words. Here, a data word refers to a sequence
of bits. "Parity" denotes the number of bits assigned as 1 in the data word, and is
designated "even" when the number of bits is even; otherwise "odd".
Password
General: Data is protected from unauthorized users by a password. If the
password is known, the rights secured by it are guaranteed. If the password is the
sole means of securing against trespassers, special measures should be taken to
keep it secret.
Bluetooth
the user for protection from unauthorized access. Bluetooth
password to calculate "link keys" with additional information that forms the basis
for authentication and encryption.
®
context: The password is a character string that can be determined by
WAGO-I/O-SYSTEM 750
750-644 Bluetooth
®
Version 2.0.0, valid from FW/HW Version 03/03
®
RF-Transceiver
SPP devices use a
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