1. Why Search and Replace Are Vital in Vi When working with HDL files, SDC constraints, or simulation logs, you often need to: Vi provides fast and flexible commands for searching and replacing text without leaving the terminal. 2. Searching for Text Command Description /pattern Search forward for the given pattern ?pattern Search backward for […]
Post 4: Search and Substitution in Vi Editor Read More »
1. Why Navigation Matters in Vi When editing large RTL, log, or constraint files, you often need to: Vi’s navigation commands are entirely keyboard-based — no mouse, no lag — ideal for SSH or terminal-only environments used in VLSI projects. 2. Basic Cursor Movement Commands Command Description h Move left by one character l Move
Post 3: Cursor Movement and Navigation in Vi Editor Read More »
1. Entering Insert Mode Vi starts in Normal Mode. To type or modify text, you must switch to Insert Mode using any of the following commands: Command Action i Insert text before the cursor I Insert text at the beginning of the current line a Append text after the cursor A Append text at the
Post 2: Insert and Edit Commands in Vi Editor Read More »
1. What is Vi/Vim Editor? Vi (Visual Editor) is one of the most powerful and lightweight text editors available on every Unix/Linux system. Its improved version, Vim (Vi Improved), adds color highlighting, syntax support, and advanced features. Vim is the go-to editor for VLSI engineers working with RTL code, constraint files, testbench scripts, or log
Post 1: Introduction to Vi/Vim Editor Read More »
Ack/Nak protocol, sequence numbering, and replay logic explained 1 . Introduction The Data Link Layer (DLL) sits between the Transaction Layer (TL) and the Physical Layer (PHY). Its core responsibility is reliability — ensuring that every TLP transmitted over the serial link is received exactly once, and without corruption. Even though the Physical Layer may introduce
Post 7.1 – Data Link Layer in PCI Express: Ensuring Reliable Delivery Read More »
Understanding live credit flow, link stalls, and verification strategies 1 . Introduction Flow control in PCIe is invisible during normal operation — it works silently behind every packet.However, debugging or verifying PCIe requires you to see how credits move and confirm that every transmission follows the credit rules. In this post, you’ll walk through real
Post 6.7 – Credit Tracking Example and Debugging in PCI Express Read More »
Traffic prioritization, VC architecture, and independent flow control 1 . Introduction So far, all our examples have used a single Virtual Channel (VC0).However, PCI Express supports multiple Virtual Channels, each functioning as a logically independent pathway through the same physical link. Every VC has its own flow control, credits, and arbitration logic, allowing multiple types
Post 6.6 – Virtual Channels and Credit Separation in PCI Express Read More »
1. Introduction The header of a Transaction Layer Packet (TLP)** is the most critical section of the PCI Express data path** — it defines what kind of transaction is being performed, where it is going, and how it should be handled.Unlike older PCI buses, where control signals were transmitted on dedicated lines, PCIe Encodes all
Chapter 5.3 – Generic TLP Header Format: Fields, Encoding, and Interpretation Read More »
When and how a TLP is allowed to transmit 1 . Introduction Once both link partners have exchanged and initialized their credits (as covered in Post 6.4), the transmitter can begin sending Transaction Layer Packets (TLPs). But not every packet can leave immediately — each TLP must first pass a flow-control check.These rules keep the
Chapter 6.5 – Transmission Rules and Credit Consumption in PCI Express Read More »
How credits are exchanged, refreshed, and maintained using DLLPs 1 . Introduction After link training completes and both ends enter the L0 state, PCI Express devices must synchronize their buffer availability before any TLPs can be exchanged. This is achieved through Flow Control Initialization — a process in which each receiver advertises how many header
Chapter 6.4 – Flow Control Initialization and Update Mechanism in PCI Express Read More »
