YiFive is a 32 bit RISC V based SOC design targeted for efabless Shuttle program. This project uses only open source tool set for simulation,synthesis and backend tools. The SOC flow follow the openlane methodology and SOC environment is compatible with efabless/carvel methodology.
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* Open sourced under Apache-2.0 License (see LICENSE file) - unrestricted commercial use allowed.
* industry-grade and silicon-proven Open-Source RISC-V core from syntacore
* industry-graded and silicon-proven 8-bit SDRAM controller
* Quad SPI Master
* UART with 16Byte FIFO
* I2C Master
* Wishbone compatible design
* Written in System Verilog
* Open-source tool set
* simulation - iverilog
* synthesis - yosys
* backend/sta - openlane tool set
* Verification suite provided.
YiFive SOC Integrated Syntacore SCR1 Open-source RISV-V compatible MCU-class core. It is industry-grade and silicon-proven IP. Git link: https://github.com/syntacore/scr1
* RV32I or RV32E ISA base + optional RVM and RVC standard extensions
* Machine privilege mode only
* 2 to 4 stage pipeline
* Optional Integrated Programmable Interrupt Controller with 16 IRQ lines
* Optional RISC-V Debug subsystem with JTAG interface
* Optional on-chip Tightly-Coupled Memory
Due to number of pin limitation in carvel shuttle, YiFive SOC integrate 8bit SDRAM controller. This is a silicon proven IP. IP Link: https://opencores.org/projects/sdr_ctrl
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* 8/16/32 Configurable SDRAM data width
* Wish Bone compatible
* Application clock and SDRAM clock can be async
* Programmable column address
* Support for industry-standard SDRAM devices and modules
* Supports all standard SDRAM functions.
* Fully Synchronous; All signals registered on positive edge of system clock.
* One chip-select signals
* Support SDRAM with four banks
* Programmable CAS latency
* Data mask signals for partial write operations
* Bank management architecture, which minimizes latency.
* Automatic controlled refresh
RISC-V based sub system
A2
sky130A