Synplify pro vs vivado
P hysical locations on the chip, denoted by the pin names you would find in a schematic (E2, A14, VV12, or similar), are associated with the top-level ports in your hardware design, named whatever you chose to name them in the design. What does “constraining a port” mean ? The location constraints in a Vivado project are like a map of the metaphorical edge of the FPGA chip. Ī component in this case means something like “a part on the board” – the FPGA has a component and a reset button, a DDR memory chip, or an HDMI connector would each have their own component.Īn interface is a set of names for signals that connect two components – a SPI interface has a clock, chip select, and a few data lines.Īn IP preset is a pre-defined configuration of an IP core, which sets it up to work for your component. So, what are the board files even doing anyway? They take a collection of pin locations (physical locations connecting the FPGA to the rest of the board) and associate them to a component, an interface, and one or more presets. Let’s explore some of the terms that were introduced above. It’s recommended to mix-and-match these approaches, using some board file interfaces and some manually-constrained ports, applying using the technique that best supports your needs for a specific port. On the other hand, board-file-based constraints are easier to initially set up – a couple of clicks instead of a decent chunk of time spent entering names and pin locations and cross-checking between several files – and can handle applying preset configurations for extremely complex IP for you. Another alternative is to include it in another interface somewhere – you could make your own UART indicator LED by tying a transmit line to a second LED output for example. For example, if you don’t care about the third LED on a four LED bank, you just don’t have to wire it up, potentially saving some resources (admittedly in the case of these LEDs, you aren’t saving more than a couple of logic cells).
Synplify pro vs vivado manual#
When using manual constraints, you aren’t locked into using a whole interface. Also, you can switch out which LEDs are used the same way – just changing a few lines of text changes which ports things are tied to – if for example you wanted to move some of those LEDs output signals into a Pmod connector. In the case of simple I/Os, like LEDs, you just need to change the pin locations in your XDC, and in most cases can continue modifying your block design without worrying about them. The former requires making some changes to a text file while the latter requires using automated flows to apply IP configuration settings that are required by the board. Manual constraints can be easier to port from one board to another than automatic constraints. Regardless of the method used, location constraints, whether written manually or automatically generated, will always be used. Manual constraints are typed up in an XDC file (or edited from a template) using a text editor. Board-file-based constraints are created entirely within the IP integrator and generate XDC files behind the scenes. When choosing which you should use for the ports in your design, there are some tradeoffs. In Vivado block designs, there are a couple of different ways to manage the inputs and outputs of your design and which FPGA pin locations they are connected to.