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Spelling fixes by Larry Doolittle

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Clifford Wolf 2015-07-01 08:18:10 +02:00
parent 4a9fda0737
commit c22ea8fe0a
1 changed files with 10 additions and 10 deletions
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README.md
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@ -25,8 +25,8 @@ PicoRV32 is free and open hardware licensed under the [ISC license](http://en.wi
Features and Typical Applications Features and Typical Applications
--------------------------------- ---------------------------------
- Small (~1000 LUTs in a 7-Series Xilinx FGPA) - Small (~1000 LUTs in a 7-Series Xilinx FPGA)
- High fMAX (~250 MHz on 7-Series Xilinx FGPAs) - High fMAX (~250 MHz on 7-Series Xilinx FPGAs)
- Selectable native memory interface or AXI4-Lite master - Selectable native memory interface or AXI4-Lite master
- Optional IRQ support (using a simple custom ISA) - Optional IRQ support (using a simple custom ISA)
- Optional Co-Processor Interface - Optional Co-Processor Interface
@ -60,11 +60,11 @@ include one or more PicoRV32 cores together with local RAM, ROM, and
memory-mapped peripherals, communicating with each other using the native memory-mapped peripherals, communicating with each other using the native
interface, and communicating with the outside world via AXI4. interface, and communicating with the outside world via AXI4.
The optional IRQ feature can be used to react to events from the outside, implemnt The optional IRQ feature can be used to react to events from the outside, implement
fault handlers, or catch instructions from a larger ISA and emulate them in fault handlers, or catch instructions from a larger ISA and emulate them in
software. software.
The optional Pico Co-Prosessor Interface (PCPI) can be used to implement The optional Pico Co-Processor Interface (PCPI) can be used to implement
non-branching instructions in an external coprocessor. An implementation non-branching instructions in an external coprocessor. An implementation
of a core that implements the `MUL[H[SU|U]]` instructions is provided. of a core that implements the `MUL[H[SU|U]]` instructions is provided.
@ -112,7 +112,7 @@ Simple instruction-level tests from [riscv-tests](https://github.com/riscv/riscv
#### dhrystone/ #### dhrystone/
Another simple test firmware that runs the Dhrystome benchmark. Another simple test firmware that runs the Dhrystone benchmark.
#### scripts/ #### scripts/
@ -165,7 +165,7 @@ Set this to 1 to enable the Pico Co-Processor Interface (PCPI).
#### ENABLE_MUL (default = 0) #### ENABLE_MUL (default = 0)
This parameter internally enables PCPI and instantiates the `picorv32_pcpi_mul` This parameter internally enables PCPI and instantiates the `picorv32_pcpi_mul`
core that implements the `MUL[H[SU|U]]` instructions. The external CPCI core that implements the `MUL[H[SU|U]]` instructions. The external PCPI
interface only becomes functional when ENABLE_PCPI is set as well. interface only becomes functional when ENABLE_PCPI is set as well.
#### ENABLE_IRQ (default = 0) #### ENABLE_IRQ (default = 0)
@ -218,7 +218,7 @@ Cycles per Instruction Performance
*A short reminder: This core is optimized for size, not performance.* *A short reminder: This core is optimized for size, not performance.*
Unless stated otherwise, the following numbers apply to a PicoRV32 with Unless stated otherwise, the following numbers apply to a PicoRV32 with
ENABLE_REGS_DUALPORT active and connected to a memory that can accomodate ENABLE_REGS_DUALPORT active and connected to a memory that can accommodate
requests within one clock cycle. requests within one clock cycle.
The average Cycles per Instruction (CPI) is 4 to 5, depending on the mix of The average Cycles per Instruction (CPI) is 4 to 5, depending on the mix of
@ -303,7 +303,7 @@ pulse on `mem_la_read` or `mem_la_write` to indicate the start of a read or
write transaction in the next clock cycles. write transaction in the next clock cycles.
*Note: The signals `mem_la_read`, `mem_la_write`, and `mem_la_addr` are driven *Note: The signals `mem_la_read`, `mem_la_write`, and `mem_la_addr` are driven
by combinatorical circuits within the PicoRV32 core. It might be harder to by combinatorial circuits within the PicoRV32 core. It might be harder to
achieve timing closure with the look-ahead interface than with the normal achieve timing closure with the look-ahead interface than with the normal
memory interface described above.* memory interface described above.*
@ -389,8 +389,8 @@ and rs2 fields are ignored in all this instructions.
See [firmware/custom_ops.S](firmware/custom_ops.S) for GNU assembler macros that See [firmware/custom_ops.S](firmware/custom_ops.S) for GNU assembler macros that
implement mnemonics for this instructions. implement mnemonics for this instructions.
See [firmware/start.S](firmware/start.S) for an example implementaion of an See [firmware/start.S](firmware/start.S) for an example implementation of an
interrupt handler assember wrapper, and [firmware/irq.c](firmware/irq.c) for interrupt handler assembler wrapper, and [firmware/irq.c](firmware/irq.c) for
the actual interrupt handler. the actual interrupt handler.
#### getq rd, qs #### getq rd, qs