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==== Instruction Memory (IMEM)

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|=======================
| Hardware source file(s): | neorv32_imem.vhd | 
| Software driver file(s): | none             | _implicitly used_
| Top entity port:         | none             | 
| Configuration generics:  | _MEM_INT_IMEM_EN_ | implement processor-internal IMEM when _true_
|                          | _MEM_INT_IMEM_SIZE_ | IMEM size in bytes
|                          | _INT_BOOTLOADER_EN_ | use internal bootlodaer when _true_ (implements IMEM as ROM)
| CPU interrupts:          | none             | 
|=======================

[NOTE]
The default `neorv32_imem.vhd` HDL source file provides a _generic_ memory design that infers embedded
memory for _larger_ memory configurations. You might need to replace/modify the source file in order to use
platform-specific features (like advanced memory resources) or to improve technology mapping and/or timing.

Implementation of the processor-internal instruction memory is enabled via the processor's
_MEM_INT_IMEM_EN_ generic. The size in bytes is defined via the _MEM_INT_IMEM_SIZE_ generic. If the
IMEM is implemented, the memory is mapped into the instruction memory space and located right at the
beginning of the instruction memory space (default `ispace_base_c` = 0x00000000).

By default, the IMEM is implemented as RAM, so the content can be modified during run time. This is
required when using a bootloader that can update the content of the IMEM at any time. If you do not need
the bootloader anymore – since your application development has completed and you want the program to
permanently reside in the internal instruction memory – the IMEM is automatically implemented as _pre-intialized_
ROM when the processor-internal bootloader is disabled (_INT_BOOTLOADER_EN_ = _false_).

When the IMEM is implemented as ROM, it will be initialized during synthesis with the actual application
program image. The compiler toolchain will generate a VHDL initialization
file `rtl/core/neorv32_application_image.vhd`, which is automatically inserted into the IMEM. If
the IMEM is implemented as RAM (default), the memory will **not be initialized** at all.