README.N1213

N1213 is a configurable hard/soft core of NDS32's N12 CPU family.

Features
========

CPU Core
 - 16-/32-bit mixable instruction format.
 - 32 general-purpose 32-bit registers.
 - 8-stage pipeline.
 - Dynamic branch prediction.
 - 32/64/128/256 BTB.
 - Return address stack (RAS).
 - Vector interrupts for internal/external.
   interrupt controller with 6 hardware interrupt signals.
 - 3 HW-level nested interruptions.
 - User and super-user mode support.
 - Memory-mapped I/O.
 - Address space up to 4GB.

Memory Management Unit
 - TLB
   - 4/8-entry fully associative iTLB/dTLB.
   - 32/64/128-entry 4-way set-associati.ve main TLB.
   - TLB locking support
 - Optional hardware page table walker.
 - Two groups of page size support.
  - 4KB & 1MB.
  - 8KB & 1MB.

Memory Subsystem
 - I & D cache.
   - Virtually indexed and physically tagged.
   - Cache size: 8KB/16KB/32KB/64KB.
   - Cache line size: 16B/32B.
   - Set associativity: 2-way, 4-way or direct-mapped.
   - Cache locking support.
 - I & D local memory (LM).
   - Size: 4KB to 1MB.
   - Bank numbers: 1 or 2.
   - Optional 1D/2D DMA engine.
   - Internal or external to CPU core.

Bus Interface
 - Synchronous/Asynchronous AHB bus: 0, 1 or 2 ports.
 - Synchronous High speed memory port.
   (HSMP): 0, 1 or 2 ports.

Debug
 - JTAG debug interface.
 - Embedded debug module (EDM).
 - Optional embedded program tracer interface.

Miscellaneous
 - Programmable data endian control.
 - Performance monitoring mechanism.