Multifunctional FPGA-JTAG Overview

Multifunctional FPGA-JTAG Overview

Hardware Introduction

Currently, there are mainly two types of AMD-Xilinx FPGA-JTAG in China: one is the official development board:

Multifunctional FPGA-JTAG Overview

The second is the newly launched smart lynq (faster and more functional):

Multifunctional FPGA-JTAG Overview

The price discourages a large number of people:

Multifunctional FPGA-JTAG Overview

The second type is domestic, with various kinds that I won’t show images of. Domestic JTAG basically uses reverse-engineered Digilent onboard JTAG, implemented with FT232Hx or FT2232Hx series chips and reverse-engineered firmware. However, recently the prices of FT232Hx and FT2232Hx have skyrocketed, so today we will try something different – reverse-engineering the official development board – using FT4232Hx (compatible with FT4232HQ and FT4232HL) to implement a multifunctional JTAG:

The overall design is a minimal FT4232 system plus a level conversion chip, as shown in the system block diagram below:

Multifunctional FPGA-JTAG Overview

It provides one JTAG and three serial ports.

It supports 7 series + U+ series FPGAs, with level support for 1.5V, 1.8V, 2.5V, and 3.3V, with TCK rates exceeding 30M.

Serial ports 1 and 2 support any TTL level, with selectable 1.8V, 3.3V, and 5V on board, selectable at the position shown in the image below:

Multifunctional FPGA-JTAG Overview

Serial port 3 only supports TTL levels that are the same as the Vref level of JTAG and cannot be set. It can only be used when powered by Vref.

Firmware Programming

It’s very simple; you just need to download the software from the open-source link below:

https://github.com/suisuisi/jtag

Compression password: openfpga

Plug the USB into the computer, and the device manager will display as follows:

Multifunctional FPGA-JTAG Overview

Click the file below to complete the programming.

Multifunctional FPGA-JTAG Overview

Expansion Board

The core board above can be appropriately expanded to add interfaces, compatible with more interface forms. To reduce size, I added an expansion board:

Multifunctional FPGA-JTAG Overview

Expansion board address:

https://oshwhub.com/OpenFPGA/jtag-zhuan-jie-ban

Legacy Issues

There are no legacy issues; the main problem is that the TYPE-C connector is too difficult to solder, requiring some skill to manage…

The expansion board needs a hole for a jumper cap to conveniently select the UART level standard; this was not done in the image, but the latest version has been corrected.

Open Source Notice

Software and hardware (schematics, PCBs are all open source). I have tested the board myself, and everyone can modify and produce it themselves.

Lastly, the firmware was obtained from a certain expert and is shared at their request; it is only for learning purposes. Any disputes or issues arising from commercial use are unrelated to this public account and the personnel related to this article~

Related posts

  1. Powerful JTAG Boundary Scan 3 – Common Boundary Scan Test Software
  2. Understanding JTAG: What You Know and Don’t Know
  3. Maximizing and Finding the Second Maximum Value Using FPGA
  4. Understanding JTAG and Other Debug Interfaces
  5. JTAG Interface Surge ESD Protection Scheme
  6. Understanding Arduino UNO
  7. Using E-Paper Displays to Indicate Critical Errors and Security Breaches in IoT Nodes
  8. The Rise of ARM: A Journey Through the Innovative 1970s
  9. DIY Phosphorescence Detector and Arduino Nano Controlled Mini Plotter
  10. Ultrasound Case: Philips EPIQ7 Touchscreen and Monitor No Display on Startup
  11. Raspberry Pi IO Port Driver Development
  12. Troubleshooting JTAG Connection Issues
  13. Ultra Low-Cost FPGA JTAG Solution
  14. Hardware Design – JTAG Chain
  15. Understanding JTAG Boundary Scan Technology
  16. Understanding JTAG Interface: Key Insights
  17. What Is JTAG? Understanding Its Basics and Applications
  18. Who Moved My JTAG Port?
  19. Introduction to JTAG Basics

Leave a Comment