RISC-V waterfall diagram and hazards

The above waterfall diagram is representing a sequence of instructions that are fetched from memory and how they progress to the various stages of pipeline. In the above diagram you got program counter (P), fetch (F), decode (D), register read (R), execute (E) and register write (W). We fetch one instruction at a time. Potentially, you can fetch multiple instructions at a time, which would be a super-scalar architecture.

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The beauty of slack-based timing ECO

A timing ECO should be power, performance and area aware and that was the crux of this webinar, where we discussed several strategies about how to do effective ECO as an expert .Slack based ECO is a beautiful strategy which helps you to achieve your timing target, while helping you to reduce on power and area

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From VLSI to System Design (SoC) – The choice of SPI

SPI model is a master/slave model. There’s some SPI master which determines who gets to transmit and who gets to receive. The output from SPI master is called MOSI (Master Out Slave In). If you have 2 slaves, slave 1 and slave 2, as shown below, MOSI goes to all the slaves .Then you have another line MISO (Master In Slave Out). All the wires are connected, as shown in below image. Then you have a master only function called SCLK, which goes to all the slaves. Now also, there must be a slave select (SS) for S1 and a slave select for S2.

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PPA (power, performance, area) card

A PPA card like the above, is something which every VLSI engineer should be carrying like a business card. Why? Right from RTL to synthesis to PNR to signoff, we do things like upsize, downsize, VT swap, and many more, and all these factors impacts or tweaks your design PPA in one way or the other.
Let’s take an example of ‘downsize’

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Committed in 2011, delivered in 2018

the flowchart is what you need to understand just to be an expert in the field of VLSI and semiconductors. Every topic shown in above image is a field, and every topic has a beautiful physics behind it, which when blended with tools in a video course, becomes a master-piece

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Facts – About below open-source EDA tool

Why “integrated”? Because at lower nodes, you have to integrate other parts of the flow. Sign-off (you can see power and timing buttons below), clock tree synthesis (you can see synthesis button) must be integrated, so we have a fully integrated PnR flow that we built from day one.

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ABI – Get this one right – RISC-V is all yours..

ABI (application binary interface), as the name says, is an interface, that helps programs access system hardware and services.RISC-V architecture has 32 registers (we explained, in detail, why this architecture has 32 registers in our online course). Application programmer, can access each of these 32 registers through its ABI name, for example, you need know the value of stack pointer or move the stack pointer, all you need to do is “addi sp, sp, -16”, where ‘sp’ is the ABI name of stack pointer.

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