GRV3000D - Digital Signal Controller
Hardware
The PulseRain GRV3000D is a fixed-point digital signal controller. It features a RISC-V dual-issue in-order processor core, plus a versatile digital signal co-processor. The highlights of the GRV3000D are as following:
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6-stage pipeline that can issue and execute up to two instructions in one clock cycle
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24-bit address bus and 64-bit data bus
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A true Harvard architecture with completely separate data memory and instruction memory
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AXI4-Lite switch for peripherals
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Support two 32-bit MAC operation in one clock cycle
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Built-in DSP coprocessor (CP)
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JTAG port for Debugging
Instruction Set
The GRV3000D supports the following RISC-V instruction sets (ISA):
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RISC-V RV32I Base Integer Instruction Set, Version 2.1
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RISC-V “Zifencei”, Instruction-Fetch Fence, Version 2.0
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RISC-V “M” Standard Extension for Integer Multiplication and Division, Version 2.0
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(Optional) RISC-V "C" Standard Extension for Compressed Instructions, Version 2.0
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RISC-V “Zicsr”, Control and Status Register (CSR) Instructions, Version 2.0
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RISC-V Base Counters and Timers
DSP Coprocessor
Unlike other RISC-V DSP solutions, the DSP Coprocessor (CP) in GRV3000D triggers the DSP acceleration through RISC-V HINT, without using any additional private instructions. In this way, the DSP acceleration is non-intrusive and it does not rely on any specific compilers to function. And the DSP CP currently supports the following operations:
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Normalization for samples in block
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Absolute value for samples in block
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Negative value for samples in block
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Value clipping for samples in block
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Left logic shift for samples in block
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Right logic shift, right arithmetic shift and right arithmetic shift with rounding for samples in block
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FIR filter for samples in block, with a throughput of two samples per clock cycle
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BIQUAD cascade filter for samples in block, with a throughput of three clock cycles per BIQUAD
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Dot Product (Real and Complex)
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FFT (Fast Fourier Transform
And the DSP Coprocessor from GRV3000D can offer unrivaled performance. Here is a FFT performance matrix for the GRV3000D against ARM Cortex-M:
Software Library
To further facilitate the adoption of the GRV3000D in DSP applications, an open-source software library called PMSIS (PulseRain Microcontroller Software Interface Standard) is also provided to the general public for free. And this library can be found in GitHub at https://github.com/PulseRain/PMSIS