xvcd – The Xilinx Virtual Cable Daemon
http://debugmo.de/2012/02/xvcd-the-xilinx-virtual-cable-daemon/
I recently discovered an almost undocumented function in Xilinx ISE: the Xilinx virtual cable driver. It’s basically “a platform cable without a platform cable” (as marcan said so nicely) – it allows you use Impact (and Chipscope, and all other tools) over TCP/IP.
Normally, ISE comes with a limited set of cable drivers: It supports cables on the parallel port, such as the Xilinx Parallel Cable III (DLC5), which can be DIY’ed easily, or the faster Xilinx Parallel Cable IV (which has an integrated CPLD), or the – quite expensive, but also sophisticated – USB Platform cables. There are also cheap clones of the platform cables (the first version used an FX2+CPLD), which I won’t link to, and then there’s Digilent Inc., which build actually useful FPGA development board, which have a USB platform cable on board (like the very cool, but slightly outdated Spartan-3A starter kit). Unfortunately, the USB platform cable itself is mysteriously missing in the schematics. Newer boards as the Digilent Atlys or the Avnet Spartan-6 LX9 MicroBoard (an, excuse me, terrible board – but that aside) don’t have the clumsy and expensive FX2+CPLD combination anymore. Instead, they come with a cheaper solution and a corresponding plugin for the Xilinx tools. However, the plugin SDK is not available publicly, so it’s not easily possible to write a plugin for arbitrary JTAG dongles (like a generic FTDI 2232 board) without either licensing the SDK or reversing the API.
For OpenVizsla I wanted to get programming working from Impact. Programming the CPLD and FPGA is supported via an on-board FTDI chip, and usually done with urjtag. However, you can’t use – for example – Chipscope.
There are solutions like this neat hack, which basically LD_PRELOADs into ISE, pretends to be libusb, provides a virtualized platform cable, and then talks to some different back end.
But it turns out – there’s a much easier, albeit undocumented, solution. It’s called xilinx_xvc, or “Xilinx Virtual Cable”. It’s a plugin – the only one next to the Digilent plugin – that can be used as a cable. It opens a TCP connection to a specific host, and sends JTAG “shift” instructions over TCP. The protocol is really, really simple: There’s only one command that I ever saw being used, calledshift:
. After that, a 32-bit little endian word specifies the number of bits, and after that, two byte-padded strings are the bits to be shifted out on TMS and TDI (in that order). The response is a byte-padded string of the bits shifted out on TDO. That’s all – a nice, abstracted JTAG PHY.
I implemented a client for this for the awesome NeTV here (requires some hardware hacking though to get the JTAG pins connected), and a generic FTDI version (based on libftdi) here (feel free to merge and send me a pull request!).
The xvcd is a daemon that listens on port 2542, and allows multiple programs to access the JTAG chain at the same point (it switches between them only when it’s “safe”; it relies on the programs to idle the chain every once in a while by going through TLR and then staying in RTI). It also works around a weirdness where Impact, whenever an IR or DR is written, goes back to the Capture-IR/DR state before exiting back to RTI (which almost always screws up the register). xvcd follow the JTAG state machine and just ignores this these instructions.
xvcd – The Xilinx Virtual Cable Daemon的更多相关文章
- Xilinx Zynq FPGA Boards板
Xilinx Zynq FPGA Boards板 Xilinx Zynq FPGA Boards 介绍 Styx是一个易于使用的Zynq开发模块,具有Xilinx的Zynq ZC7020 SoC和FT ...
- 2.Kali安装VMware tools(详细+异常处理)
dnt@MT:~$ cd /media/cdrom0 进入光驱内 dnt@MT:/media/cdrom0$ ls 查看当前目录下有哪些内容manifest.txt run_upgrader.sh V ...
- 【转】虚拟机VMware与主机共享文件介绍
from: http://www.cnblogs.com/kerrycode/p/3818095.html 写的比较详细,但是vm版本较旧. 2:通过共享文件夹功能 虚拟机VMware提供了在宿主机与 ...
- Oracle Linux 5.7安装VMware Tools的问题
案例环境介绍: 虚拟机的版本:VMware® Workstation 8.0.3 build-703057 操作系统版本:Oracle Linux Server release 5.7 ...
- 虚拟机VMware与主机共享文件介绍
我们经常会在Windows平台安装虚拟机VMware,不管是出于实验测试还是工作需要,伴随而来的就是经常需要在Windows系统和虚拟机系统之间进行共享数据文件,例如,需要将Window主机上的Ora ...
- 【转】linux network namespace 学习
原文地址:https://segmentfault.com/a/1190000004059167 介绍 在专业的网络世界中,经常使用到Virtual Routing and Forwarding(VR ...
- VM的Linux CentOS系统的VMTools的手动安装
VM的Linux CentOS系统的VMTools的手动安装 一是没时间安装,另外是一直用的是VM的绿色版,里面没有Linux.iso 文件 今天晚上安装上了 linux 的vmtools ,再也不用 ...
- ZYNQ-7000 Unable to connect to ps7_cortexa9 解决方案
图1 开发工具:Xilinx SDk 14.4(基于Eclipse,ISE suite 14.4组件之一) 开发板:Xilinx ZYNQ-7000 zc702 rev 1.0(注意:这个板子的版本说 ...
- 如何在windows xp下实现声音内录
问题描述: 用屏幕录制软件录制一个视频,能够成功录制视频,但无法录制视频里面的声音. 问题原因: 因为现在的多数声卡,均无法直接通过声卡自身的功能实现内录和立体声混音. 这是由于声卡芯片厂商迫于RIA ...
随机推荐
- 数据库-mysql中文显示问题
一:在mysql 下面查看带中文的记录显示乱码 mysql> select * from role; +----+------+ | id | name | +----+------+ | 1 ...
- Densely Connected Convolutional Networks 论文阅读
毕设终于告一段落,传统方法的视觉做得我整个人都很奔溃,终于结束,可以看些搁置很久的一些论文了,嘤嘤嘤 Densely Connected Convolutional Networks 其实很早就出来了 ...
- java基础30 List集合下的LinkedList集合
单例集合体系: ---------| collection 单例集合的根接口--------------| List 如果实现了list接口的集合类,具备的特点:有序,可重复 注:集合 ...
- group by 并且 count(1)的linq写法
SELECT [MobleNo],count(1) FROM [CustMobleNo] group by [MobleNo] GO ===作用等于=== var rst = from c in da ...
- 每位架构师都应该熟知的 10 个 SOA 设计模式
这 10 个 SOA 设计模式是如此之重要,其应用是如此之广泛,以至于它们都有些显而易见了. 1. 服务无关 服务无关实现对多种业务通用的逻辑.将服务无关的逻辑分离成离散的服务以方便服务的重用和整合. ...
- cross apply 和 outer apply
使用APPLY运算符可以实现查询操作的外部表表达式返回的每个调用表值函数.表值函数作为右输入,外部表表达式作为左输入. 通过对右输入求值来获得左输入每一行的计算结果,生成的行被组合起来作为最终输出.A ...
- SQL Server 2000 系统存储过程
SQL Server 2000 系统存储过程 在 Microsoft? SQL Server? 中,许多管理和信息活动可以通过系统存储过程执行.系统存储过程按这些分类分组. 分类 描述 Active ...
- The Art Of Computer Programming: 1.1
The Art Of Computer Programming: 1.1 */--> div.org-src-container { font-size: 85%; font-family: m ...
- Pg168-1
1.Pg168-1 package org.hanqi.pn0120; public class Computer { private double neicundx=10; public doubl ...
- 何时调用getView?——从源码的角度给出解答
先来看ListView类中的makeAndAddView方法: 没有数据变化:从mRecycler中取得可视的view 数据有变化:obtainView /** * 获取视图填充到列表的item中去, ...