### Timer Instruction Format Source: https://github.com/yosyshq/picorv32/blob/main/README.md Instruction format and example for the PicoRV32 timer. ```text 0000101 ----- XXXXX --- XXXXX 0001011 f7 rs2 rs f3 rd opcode ``` ```text timer x1, x2 ``` -------------------------------- ### Custom Instruction Encoding and Usage Source: https://github.com/yosyshq/picorv32/blob/main/README.md Shows the bit-field encoding for custom instructions and an example of the getq instruction usage. ```text 0000000 ----- 000XX --- XXXXX 0001011 f7 rs2 qs f3 rd opcode ``` ```asm getq x5, q2 ``` -------------------------------- ### Build Toolchain Commands Source: https://github.com/yosyshq/picorv32/blob/main/README.md Commands to download and build the complete toolchain. ```bash make download-tools make -j$(nproc) build-tools ``` -------------------------------- ### Build LED-blinking firmware and timing report Source: https://github.com/yosyshq/picorv32/blob/main/scripts/icestorm/readme.md Compiles the firmware for the HX8K Breakout Board and generates a timing report based on the 12MHz oscillator. ```bash $ make clean example.bin timing ``` -------------------------------- ### PicoRV32 Makefile Targets Source: https://github.com/yosyshq/picorv32/blob/main/README.md Available make targets for building specific RV32 toolchains. ```bash make -j$(nproc) build-riscv32i-tools make -j$(nproc) build-riscv32ic-tools make -j$(nproc) build-riscv32im-tools make -j$(nproc) build-riscv32imc-tools ``` ```bash make -j$(nproc) build-tools ``` ```bash make download-tools ``` -------------------------------- ### Build Pure RV32I Toolchain Source: https://github.com/yosyshq/picorv32/blob/main/README.md Detailed steps to build the RISC-V GNU toolchain for a pure RV32I target. ```bash # Ubuntu packages needed: sudo apt-get install autoconf automake autotools-dev curl libmpc-dev \ libmpfr-dev libgmp-dev gawk build-essential bison flex texinfo \ gperf libtool patchutils bc zlib1g-dev git libexpat1-dev sudo mkdir /opt/riscv32i sudo chown $USER /opt/riscv32i git clone https://github.com/riscv-collab/riscv-gnu-toolchain riscv-gnu-toolchain-rv32i cd riscv-gnu-toolchain-rv32i git checkout 411d134 git submodule update --init --recursive mkdir build; cd build ../configure --with-arch=rv32i --prefix=/opt/riscv32i make -j$(nproc) ``` -------------------------------- ### Navigate Tcl Console Directories Source: https://github.com/yosyshq/picorv32/wiki/Programming-the-Nexys-4-DDR-Artix-7-FPGA-Trainer-Board Use standard Tcl commands to manage the working directory within the Vivado Tcl console. ```tcl cd ``` ```tcl pwd ``` -------------------------------- ### Run simulation tests Source: https://github.com/yosyshq/picorv32/blob/main/scripts/icestorm/readme.md Executes simulation tests with a specified counter bit parameter. The clean target is required to ensure the firmware is rebuilt correctly for simulation. ```bash $ make clean example_sim synth_sim route_sim FIRMWARE_COUNTER_BITS=4 ``` -------------------------------- ### Pico Co-Processor Interface (PCPI) Signals Source: https://github.com/yosyshq/picorv32/blob/main/README.md Lists the input and output signals required to implement non-branching instructions in external co-processor cores. ```verilog output pcpi_valid output [31:0] pcpi_insn output [31:0] pcpi_rs1 output [31:0] pcpi_rs2 input pcpi_wr input [31:0] pcpi_rd input pcpi_wait input pcpi_ready ``` -------------------------------- ### PicoRV32 Native Memory Interface Signals Source: https://github.com/yosyshq/picorv32/blob/main/README.md The native memory interface uses a valid-ready handshake protocol for memory transfers. ```verilog output mem_valid output mem_instr input mem_ready output [31:0] mem_addr output [31:0] mem_wdata output [ 3:0] mem_wstrb input [31:0] mem_rdata ``` -------------------------------- ### setq qd, rs Source: https://github.com/yosyshq/picorv32/blob/main/README.md Copies the value from a general-purpose register to a q-register. ```APIDOC ## setq qd, rs ### Description Copies the value from a general-purpose register to a q-register. ### Example setq q2, x5 ``` -------------------------------- ### Set Q-Register Instruction Source: https://github.com/yosyshq/picorv32/blob/main/README.md Copies a value from a general-purpose register to a q-register. ```assembly setq q2, x5 ``` -------------------------------- ### Configure XDC Constraints for Nexys 4 DDR Source: https://github.com/yosyshq/picorv32/wiki/Programming-the-Nexys-4-DDR-Artix-7-FPGA-Trainer-Board Define pin assignments and clock constraints for the Nexys 4 DDR board in the XDC file. ```xdc # XDC File for Nexys 4 DDR Board ########################### set_property PACKAGE_PIN D5 [get_ports clk] set_property IOSTANDARD LVCMOS33 [get_ports clk] create_clock -period 10.00 [get_ports clk] # Pmod Header JA (JA0..JA7) set_property PACKAGE_PIN K1 [get_ports {out_byte[0]}] set_property IOSTANDARD LVCMOS33 [get_ports {out_byte[0]}] set_property PACKAGE_PIN J3 [get_ports {out_byte[1]}] set_property IOSTANDARD LVCMOS33 [get_ports {out_byte[1]}] set_property PACKAGE_PIN J2 [get_ports {out_byte[2]}] set_property IOSTANDARD LVCMOS33 [get_ports {out_byte[2]}] set_property PACKAGE_PIN G2 [get_ports {out_byte[3]}] set_property IOSTANDARD LVCMOS33 [get_ports {out_byte[3]}] set_property PACKAGE_PIN H1 [get_ports {out_byte[4]}] set_property IOSTANDARD LVCMOS33 [get_ports {out_byte[4]}] set_property PACKAGE_PIN K2 [get_ports {out_byte[5]}] set_property IOSTANDARD LVCMOS33 [get_ports {out_byte[5]}] set_property PACKAGE_PIN H2 [get_ports {out_byte[6]}] set_property IOSTANDARD LVCMOS33 [get_ports {out_byte[6]}] set_property PACKAGE_PIN G3 [get_ports {out_byte[7]}] set_property IOSTANDARD LVCMOS33 [get_ports {out_byte[7]}] # Pmod Header JB (JB0..JB2) set_property PACKAGE_PIN A14 [get_ports {resetn}] set_property IOSTANDARD LVCMOS33 [get_ports {resetn}] set_property PACKAGE_PIN A16 [get_ports {trap}] set_property IOSTANDARD LVCMOS33 [get_ports {trap}] set_property PACKAGE_PIN B14 [get_ports {out_byte_en}] set_property IOSTANDARD LVCMOS33 [get_ports {out_byte_en}] ``` -------------------------------- ### Look-Ahead Memory Interface Signals Source: https://github.com/yosyshq/picorv32/blob/main/README.md Defines the output signals for the Look-Ahead Memory Interface, which provides memory transfer information one clock cycle early. ```verilog output mem_la_read output mem_la_write output [31:0] mem_la_addr output [31:0] mem_la_wdata output [ 3:0] mem_la_wstrb ``` -------------------------------- ### Return from Interrupt Instruction Source: https://github.com/yosyshq/picorv32/blob/main/README.md Copies the value from q0 to the program counter and re-enables interrupts. ```assembly retirq ``` -------------------------------- ### Update Vivado Synthesis Target Device Source: https://github.com/yosyshq/picorv32/wiki/Programming-the-Nexys-4-DDR-Artix-7-FPGA-Trainer-Board Modify the synth_design command in the Tcl script to match the specific FPGA part on the Nexys 4 DDR board. ```tcl synth_design -part xc7k70t-fbg676 -top system ``` ```tcl synth_design -part xc7a100tcsg324-1 -top system ``` -------------------------------- ### retirq Source: https://github.com/yosyshq/picorv32/blob/main/README.md Return from interrupt. Copies the value from q0 to the program counter and re-enables interrupts. ```APIDOC ## retirq ### Description Return from interrupt. This instruction copies the value from q0 to the program counter and re-enables interrupts. ### Example retirq ``` -------------------------------- ### Wait for Interrupt Instruction Source: https://github.com/yosyshq/picorv32/blob/main/README.md Pauses execution until an interrupt becomes pending, writing the pending IRQ bitmask to the destination register. ```assembly waitirq x1 ``` -------------------------------- ### waitirq rd Source: https://github.com/yosyshq/picorv32/blob/main/README.md Pause execution until an interrupt becomes pending. The bitmask of pending IRQs is written to rd. ```APIDOC ## waitirq rd ### Description Pause execution until an interrupt becomes pending. The bitmask of pending IRQs is written to rd. ### Example waitirq x1 ``` -------------------------------- ### maskirq rd, rs Source: https://github.com/yosyshq/picorv32/blob/main/README.md Writes a new value to the IRQ mask register and reads the old value. ```APIDOC ## maskirq rd, rs ### Description The IRQ Mask register contains a bitmask of masked (disabled) interrupts. This instruction writes a new value to the irq mask register and reads the old value. ### Example maskirq x1, x2 ``` -------------------------------- ### Mask Interrupts Instruction Source: https://github.com/yosyshq/picorv32/blob/main/README.md Writes a new value to the IRQ mask register and reads the previous value. ```assembly maskirq x1, x2 ``` === COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.