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GR716-DS-UM, May 2019, Version 1.29
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www.cobham.com/gaisler
GR716
16.7
Software considerations
16.7.1 Register file initialization on power up for LEON3FT
This section is only valid if internal boot ROM is bypassed.
After power-on and internal boot ROM is bypassed, the check bits in the IU and FPU register files are
not initialized. This means that access to an un-initialized (un-written) general-purpose register could
cause a register access trap (tt = 0x20). Such behavior is considered as a software error, as the soft-
ware should not read a register before it has been written. It is recommended that the boot code for the
processor writes all registers in the IU and FPU register files before launching the main application.
Initialization of IU and FPU register files is performed by the internal boot ROM before handover to
application software.