Ingenico IUC150B - 4.3 Operating system

Integration guide iUC150B & iUC160B
900021059 R11 000 04/0416
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4_3 Operating system
Bootstrap
Bootstrap is resident.
The bootstrap very briey takes control of the terminal after each power up to perform the initialization
and the self-test. Then, it automatically runs the operating system, which in turn starts the applications
manager.
Thus, the Bootstrap provides the following functionalities:
Memory and checksum self-test
Local download of the operating system if absent
Operating system authenticity check and start-up.
Operating system (OS) characteristics
The operating system is downloaded (locally or remotely) into the memory. It is upgradeable. After
a few fractions of a second following a power-up, the operating system takes control. It checks the
presence, integrity and authenticity of the system components and application software present in the
terminal.
The maintenance sub-system takes control in the following cases:
if no authentic application is present,
or, if a manual action is made by the operator during power up,
or, if it is activated by an application.
The maintenance sub-system ensures, among other things, the downloading of the application software.
The operating system ensures the start of the multi-task core and then runs the applications by making
a set of services available to them:
Multi-task management: Availability of a pre-emptive real-time environment, based on
interruptions, events and mailboxes. This management enables simultaneous processing, which
improves the terminal’s performance.
Input/Output management: This is carried out under interruptions, generally in buffered mode.
Thus, the application developer enters a “conventional” C context.
System alarm management: Certain incidents detected by the operating system are recorded.
They can be used later by the maintenance sub-system during remote or local diagnostics.
Application alarm management: A number of incidents detected by the applications can be
saved by the operating system at their request. This recording is used later as in the case of
system alarms.
Application isolation management: The operating system provides the mechanisms described
in the section on software isolation and memory protection.
Inter-application isolation is managed by the Memory Management Unit (MMU).
Application download management: The operating system offers the downloading services
described in the « Software download » section.