In TCL FPGA Wizards Trust
In TCL FPGA wizards trust. The best way to learn TCL is exposure therapy which we will be doing here using two examples: One for creation of a project with synthesis and implementation steps and another for simulation.
Linear Feedback Shift Registers for the Uninitiated
Jason Sachs assembled an eighteen-part deep dive into linear feedback shift registers, connecting the simple shift-register circuit to finite-field algebra and practical tools. The series walks through primitive polynomials, Berlekamp-Massey state recovery, libgf2-based analysis, discrete-log methods, and real-world uses from PRNGs and Gold codes to Reed-Solomon and CRC reverse-engineering. It’s a single reference for engineers who want both theory and working code.
How to Implement Image Processing Algorithms in FPGA Hardware
Recognized for their parallelism and reconfigurability, FPGAs prove ideal for real-time processing in medical imaging and computer vision. The step-by-step approach starts with understanding FPGA basics, emphasizing their reconfigurable nature and parallel processing. It guides users in algorithm selection based on factors like processing speed, resource utilization, and adaptability, then highlights designing modular and scalable algorithms. The process includes simulation for verification, synthesis using tools like Xilinx Vivado and Intel Quartus Prime, interfacing with image sensors, and testing on real hardware. The conclusion underscores FPGA's advantages in image processing, presenting ongoing opportunities for innovation in diverse industries.
Square root in fixed point VHDL
In this blog we will design and implement a fixed point square root function in VHDL. The algorithm is based on the recursive Newton Raphson inverse square root algorithm and the implementation offers parametrizable pipeline depth, word length and the algorithm is built with VHDL records and procedures for easy use.
Mastering Modern FPGA Skills for Engineers
In the rapidly evolving tech industry, engineers must acquire proficiency in modern FPGA skills. These skills empower engineers to optimize designs, minimize resource usage, and efficiently address FPGA design challenges while ensuring functionality, security, and compliance.
FPGA skills for the modern world
FPGA demand is booming across industries from automotive to edge AI, and employers want engineers who can think in hardware. This post explains the mindset shift to RTL-level, concurrent design, waveform-based debugging with ILAs, and modern verification flows. It also highlights the practical skills that make you marketable, including HDLs, SoC/Linux integration, RISC-V know-how, and high-speed design techniques.
Three more things you need to know when transitioning from MCUs to FPGAs
Take a look at three more important difference between FPGAs and MCUs: "code reuse" vs templating, metastability and blocking vs. non-blocking operations.
Jumping from MCUs to FPGAs - 5 things you need to know
Are you a microcontroller expert beckoned by the siren song of the FPGA? Not long ago, that was me. FPGA-expert friends of mine regularly extolled the virtues of these mysterious components and I wanted in. When I made the leap, I found a world seemingly very familiar, but in reality, vastly different. I found that my years of C programming and microcontroller use often gave pre preconceived interpretations of FPGA resource material which resulted in eye-roll class mistakes in my code. I’ve gleaned five things of vital importance to help you make that transition faster than I did.
Linear Feedback Shift Registers for the Uninitiated, Part X: Counters and Encoders
Jason Sachs shows how linear feedback shift registers can be practical counters and compact absolute encoders, and why the choice of polynomial matters. He explains using primitive and reducible polynomials to get long but decode-friendly periods, demonstrates a 48-bit example, and lays out a De Bruijn chain-code encoder that turns an extra track into quick absolute resynchronization. Read to learn implementation tradeoffs and decoding strategies.
Linear Feedback Shift Registers for the Uninitiated, Part I: Ex-Pralite Monks and Finite Fields
Jason Sachs demystifies linear feedback shift registers with a practical, bitwise view and the algebra that explains why they work. Readable examples compare Fibonacci and Galois implementations, show a simple software implementation, and reveal the correspondence between N-bit Galois LFSRs and GF(2^N) so you can pick taps and reason about maximal-length pseudorandom sequences.
VHDL tutorial
Gene Breniman presents a hands-on VHDL walkthrough for a programmable clock divider implemented on a Xilinx CoolRunner CPLD (XC2C32A). The example shows how to declare ports and internal signals, implement a clock-division process with reset and falling-edge detection, and create a simple addressable latch to select clock rates from a 40MHz master clock. It’s a compact, practical guide for embedded engineers learning VHDL and CPLD design.
VHDL tutorial - Creating a hierarchical design
Complex VHDL files quickly become hard to read and maintain. This tutorial demonstrates how to break a design into reusable entities by building a divide-by-10 component, explaining ports, sensitivity lists, and the inout usage for a toggled output. It then shows how to instantiate and chain three instances into a ÷1000 divider, with synthesis notes from compiling to an XC2C128 device.
VHDL tutorial - A practical example - part 1 - Hardware
Gene Breniman walks through a practical CPLD-based data acquisition engine built for a low-power handheld instrument, focusing on hardware choices, signal flow, and pin assignments. The article explains component selection including a PCM1870 ADC, CY14B101Q2 serial nvSRAM, and an XC2C64A CPLD, and shows how the CPLD acts as an SPI sequencer and I2S clock master while minimizing microcontroller pins and power draw.
VHDL tutorial - A practical example - part 2 - VHDL coding
Gene Breniman walks through the VHDL coding for a CPLD-based data acquisition engine, turning the hardware spec into a working state machine and signal generators. The article explains SPI and I2S timing choices, an internal SPI peripheral latch, and counter-based timing (seqCount and CycleCnt) used to create LRCK, BCK, SPI SCK and nvSRAM write control. It’s a practical, implementation-focused guide for embedded designers.
VHDL tutorial - A practical example - part 3 - VHDL testbench
Gene Breniman walks a complete VHDL testbench workflow for a CPLD-based data acquisition engine, from Xilinx ISE testbench generation to stimulus processes. He shows clock and SPI gating, a simulated ADC data generator tied to ADC_LRCK and ADC_BCK, and how simulation revealed a timing bug in the nvSRAM header that was then fixed in the VHDL. Practical and hands-on for verification work.
VHDL tutorial - part 2 - Testbench
In this follow-up Gene Breniman builds a VHDL testbench in Xilinx ISE, showing how to generate a continuous master clock, apply a power-on reset, and sequence register strobes to change clock divisors. He walks through timing waits and observation delays needed to verify ADC clock rates. The article also shows how simulation exposed a copy-paste bug in the original design.
VHDL tutorial - combining clocked and sequential logic
Need the ADC clock to sometimes be the raw 40MHz input? Gene Breniman shows how to extend a reloadable, counter-based VHDL clock divider to support a master-clock pass-through by using a conditional signal assignment to switch between the internal ADCClk and Mclk. The article also covers remapping ClkSel values and includes a working XC2C32A CPLD build that leaves room for future enhancements.
How FPGAs work, and why you'll buy one
Yossi Kreinin argues that FPGAs are no longer just programmable gate arrays, they are becoming a mainstream programmable acceleration and I/O platform. The article explains how modern FPGAs pair a sea of LUTs and switch boxes with DSP slices, RAMs, and hard CPUs to deliver massive parallelism, deterministic timing, and surprising energy efficiency, and it includes a readable Verilog convolution example to show how this works in practice.
Linear Feedback Shift Registers for the Uninitiated, Part I: Ex-Pralite Monks and Finite Fields
Jason Sachs demystifies linear feedback shift registers with a practical, bitwise view and the algebra that explains why they work. Readable examples compare Fibonacci and Galois implementations, show a simple software implementation, and reveal the correspondence between N-bit Galois LFSRs and GF(2^N) so you can pick taps and reason about maximal-length pseudorandom sequences.
FPGA skills for the modern world
FPGA demand is booming across industries from automotive to edge AI, and employers want engineers who can think in hardware. This post explains the mindset shift to RTL-level, concurrent design, waveform-based debugging with ILAs, and modern verification flows. It also highlights the practical skills that make you marketable, including HDLs, SoC/Linux integration, RISC-V know-how, and high-speed design techniques.
VHDL tutorial - A practical example - part 3 - VHDL testbench
Gene Breniman walks a complete VHDL testbench workflow for a CPLD-based data acquisition engine, from Xilinx ISE testbench generation to stimulus processes. He shows clock and SPI gating, a simulated ADC data generator tied to ADC_LRCK and ADC_BCK, and how simulation revealed a timing bug in the nvSRAM header that was then fixed in the VHDL. Practical and hands-on for verification work.
How FPGAs work, and why you'll buy one
Yossi Kreinin argues that FPGAs are no longer just programmable gate arrays, they are becoming a mainstream programmable acceleration and I/O platform. The article explains how modern FPGAs pair a sea of LUTs and switch boxes with DSP slices, RAMs, and hard CPUs to deliver massive parallelism, deterministic timing, and surprising energy efficiency, and it includes a readable Verilog convolution example to show how this works in practice.
VHDL tutorial - part 2 - Testbench
In this follow-up Gene Breniman builds a VHDL testbench in Xilinx ISE, showing how to generate a continuous master clock, apply a power-on reset, and sequence register strobes to change clock divisors. He walks through timing waits and observation delays needed to verify ADC clock rates. The article also shows how simulation exposed a copy-paste bug in the original design.
VHDL tutorial
Gene Breniman presents a hands-on VHDL walkthrough for a programmable clock divider implemented on a Xilinx CoolRunner CPLD (XC2C32A). The example shows how to declare ports and internal signals, implement a clock-division process with reset and falling-edge detection, and create a simple addressable latch to select clock rates from a 40MHz master clock. It’s a compact, practical guide for embedded engineers learning VHDL and CPLD design.
VHDL tutorial - A practical example - part 2 - VHDL coding
Gene Breniman walks through the VHDL coding for a CPLD-based data acquisition engine, turning the hardware spec into a working state machine and signal generators. The article explains SPI and I2S timing choices, an internal SPI peripheral latch, and counter-based timing (seqCount and CycleCnt) used to create LRCK, BCK, SPI SCK and nvSRAM write control. It’s a practical, implementation-focused guide for embedded designers.
VHDL tutorial - Creating a hierarchical design
Complex VHDL files quickly become hard to read and maintain. This tutorial demonstrates how to break a design into reusable entities by building a divide-by-10 component, explaining ports, sensitivity lists, and the inout usage for a toggled output. It then shows how to instantiate and chain three instances into a ÷1000 divider, with synthesis notes from compiling to an XC2C128 device.
VHDL tutorial - A practical example - part 1 - Hardware
Gene Breniman walks through a practical CPLD-based data acquisition engine built for a low-power handheld instrument, focusing on hardware choices, signal flow, and pin assignments. The article explains component selection including a PCM1870 ADC, CY14B101Q2 serial nvSRAM, and an XC2C64A CPLD, and shows how the CPLD acts as an SPI sequencer and I2S clock master while minimizing microcontroller pins and power draw.
Linear Feedback Shift Registers for the Uninitiated, Part I: Ex-Pralite Monks and Finite Fields
Jason Sachs demystifies linear feedback shift registers with a practical, bitwise view and the algebra that explains why they work. Readable examples compare Fibonacci and Galois implementations, show a simple software implementation, and reveal the correspondence between N-bit Galois LFSRs and GF(2^N) so you can pick taps and reason about maximal-length pseudorandom sequences.
VHDL tutorial - combining clocked and sequential logic
Need the ADC clock to sometimes be the raw 40MHz input? Gene Breniman shows how to extend a reloadable, counter-based VHDL clock divider to support a master-clock pass-through by using a conditional signal assignment to switch between the internal ADCClk and Mclk. The article also covers remapping ClkSel values and includes a working XC2C32A CPLD build that leaves room for future enhancements.
Square root in fixed point VHDL
In this blog we will design and implement a fixed point square root function in VHDL. The algorithm is based on the recursive Newton Raphson inverse square root algorithm and the implementation offers parametrizable pipeline depth, word length and the algorithm is built with VHDL records and procedures for easy use.
