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GR716-DS-UM, May 2019, Version 1.29
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GR716
16.1.4 Interrupt interface
LEON3 supports the SPARC V8 interrupt model with a total of 15 asynchronous interrupts. The inter-
rupt interface provides functionality to both generate and acknowledge interrupts.
16.1.5 AMBA interface
LEON3 implements an AMBA AHB master to load and store data. The interface is compliant with
the AMBA-2.0 standard.
16.1.6 Power-down mode
The LEON3 processor core implements a power-down mode, which halts the pipeline until the next
interrupt. The processor also supports clock gating during the power down period. A small part of the
CPU is always awake and needs to run during power-down to check for wake-up conditions.
16.2
LEON3 integer unit
16.2.1 Overview
The LEON3 integer unit implements the integer part of the SPARC V8 instruction set. The implemen-
tation is focused on high performance and low complexity. The LEON3 integer unit has the following
main features:
•
7-stage instruction pipeline
•
31 register windows
•
Hardware multiplier
•
Radix-2 divider (non-restoring)
•
Static branch prediction
•
Single-vector trapping for reduced code size