SIMATIC IPC627D/827D 
Operating Instructions, 09/2014, A5E32990859-AB 
175 
AHCI is a standardized method to address the SATA controller. AHCI describes a structure 
in the RAM, which contains a general area for control and status, as well as a command list.  
Advanced peripheral interrupt controller. 24 interrupt lines are available. 
A programmable controller (PLC) of the SIMATIC S7 system consist of a central controller, 
one or several CPUs, and various I/O modules. 
Duplicate of a program, data medium or database, used either for archiving purposes or for 
the protection of vital and non-replaceable data against loss when the working copy is 
corrupted. Certain applications automatically generate backup copies of data files, and 
manage both the current and the previous versions on the hard disk. 
Physical unit for the step speed in signal transmission. Defines the number of transferred 
signal states per second. With only two states, one baud is equivalent to a transmission rate 
of 1 bps. 
A boot disk is a disk with a "Boot" sector. This can be used to load the operating system from 
the disk. 
High-speed access buffer for interim storage (buffering) of requested data. 
ommunauté 
uropéene The CE mark confirms compliance of the product with 
corresponding EC Directives, for example, with the EMC Directive.