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R01UH0336EJ0102 Rev.1.02
Page 349 of 1538
Jul 17, 2014
V850E2/PG4-L
Section 10 Safety Guardian (SGA)
10.2 SGA Functional Overview
The safety guardian (SGA) collects all the internal error signals coming from
the different error sources and monitoring circuits. These errors are for
instance generated by the clock monitor, ECC circuit, compare unit, and other
monitoring units.
Features
summary
The SGA has the following features.
• Error collection, status indication, and individual treatment
– Error generation via SGATERROUTZ
– Interrupt generation via SGATI
– Internal reset generation via SGARES
The SGA is implemented redundant. Some of the redundant registers are
accessed simultaneously by one write operation and some registers have to
be accessed individually. This allows an individual functional test by software
of the two safety guardian instances.
• SGA (safety guardian) register area represents the common register area
where the redundant registers are accessed simultaneously by one write
operation.
• SGAM (safety guardian master) register area represents a register area
where the SGA master registers are accessed individually.
• SGAC (safety guardian checker) register area represents a register area
where the SGA checker registers are accessed individually.
The following block diagram shows the mapping of the SGA register areas.
Figure 10-1
Register Areas of the Redundant SGA
<SGAM_base> address
<SGA_base> address
<SGAC_base> address
SGA
SGA C
SGAM