The DS requires a 5volt supply VR2. We used a cheap 3. The 5volt supply VR2 can be excluded if you use a slower L 3. The latch inputs are held low with a 1Mohm resistor network RN1. The board is a quasi one-sided design. We made several compromises so we could prototype this highly experimental PCB ourselves. One power pin of the CPLD is missing a decoupling capacitor entirely; there was no way to put a capacitor in that area. Using these through-hole parts eliminated a few jumper wires.
The jumper wires on the back of the board are optimized for single-sided production, rather than good design practices. We faked a double-sided board by soldering the power bus on the back. A real double-sided board design should route the power bus to avoid crossing signal paths, and include the missing decoupling capacitors. We used an surface mount PLCC chip socket, but a through-hole version is definitely a better idea.
We though the SMD version would be easy to solder, but it turned out to be a nightmare. We really wanted the CPLD to be on the front of the board for the coolest possible presentation.
Click here for a full size placement diagram PNG. The firmware is included in the project archive at the end of the article. We wanted a super easy way to interact with the hardware on the board without endless compile-program-test cycles.
Check out the Bus Pirate tutorial for background on the simple syntax used with the firmware. The original Bus Pirate firmware handles several protocols that share the same pins. For the CPLD version, we changed the pin assignments to fit the connections on the development board.
We also removed unused modules and options. The schematics, pin placement files, and compiled designs XSVF are included in the project archive linked at the end of the article. A full explanation of ISE is beyond the scope of this article; we found the help files sufficiently useful to make these examples. We like Tera Term and Hercules on Windows.
The default PC side setting for the development board terminal is bps, 8N1. HiZ 2. I2C 3. JTAG 4. In the terminal we enter the mode menu m , and choose JTAG 3.
The chain report tells us that the chip is connected and responding. Read more about the JTAG interface. The first example just lights the LED on pin 8. If the LED lights, we can verify that programming was successful. Advanced re-programmable devices. Simple and easy to use. Low cost. Programming kept on power down CPLD functions available instantly on system power up Almost impossible to steal stored design Improves security, simplifies design.
Designing with CPLDs. Choosing a CPLD. Performance Xilinx CPLDs come in a variety of speed grades so that you only pay for the performance you need. I don't know how it compares to other makers' products. Hello, I have sent you an e-mail to ask you if you can provide me the Eagle files for this programmer! Similar threads P. Xilinx CPLD programming. Replies 6 Views 4K. Oct 5, phalanx. Replies 2 Views Jan 24, Budi Nugroho. CPLD problem. Replies 2 Views 2K.
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Repairing Electronics. Automotive Electronics. How do you get homework help when you reach master's level of very higher level of education? Click the donate button to send a donation of any amount. This article shows how to make a new project using the Xilinx ISE software. Either start the software from the desktop icon or find it on the Windows menu as shown in this image:.
Start a new project by clicking the New Project This will open the New Project Wizard dialog box. Select the desired location of the new project and then fill in the name of the new project as shown below.
Fill in the project settings for the device and language to be used. Choose VHDL as the preferred language for this example.
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