Contents
What is a bus in PCB?
A bus is just a term for a collection of alike signals. In a schematic they will be connected to a single thick line, just as a graphical representation. I.E. You can have a data bus, all the data signals D0-D7 etc routed together, with same lengths etc. You can have an address bus, other buses etc.
What is a bus in Eagle?
We will use a tool from EAGLE called ‘Bus’ to gather signals into a logical group. Using “show” tool with this bus will highlight all signals grouped in this bus both in the schematic and the board.
What is the difference between a bus and a wire?
What differentiates a wire as not being a bus is that it only carries one coherent “entity” such as power or a microphone signal or is connected to an on/off switch or a guitar or a speaker. A bus is usually digital. I usually consider a bus a union of many wires. Imagine an address data bus with A15..
What is bus wire used for?
Bus cables or industrial communication cables are used for the digital signal transmission between sensors and the corresponding display units. Due to the high transmission rate and data flow, standard data cables are not sufficient any more.
What’s the difference between a bus and a net in Eagle?
In Eagle, buses don’t actually do very much, they just look pretty. You can however use them to keep track of which net names you a trying to route from one side of a schematic to another. Here is an example of a few Eagle buses. Basically rather than drawing individual wires for every connection, you can instead draw one bus.
How to draw a bus using a net?
With the Net tool, if you click on the bus you will see something like below. If you have any [x..x] entries as mentioned above, you will see them all grouped into a sub-menu. You can then click on any menu item to start drawing a wire in that net. Basically this is equivalent to first using the wire tool and then the name tool.
What happens if you delete a bus in nets?
You can use the wire tool to extend nets that you started drawing with the net tool. Once done you can use the label tool to display the net name to make it easy to see what is what. If you delete the bus, nothing happens, any wires that are connected to it are not deleted, nor do they change name.
How are nets and buses treated in Electrical Engineering?
In the layout they have no meaning what-so-ever, each net in the bus is treated as a separate net. You can’t route them together as a bus (e.g. if you had 8 data lines you wanted to run in parallel). Thanks for contributing an answer to Electrical Engineering Stack Exchange!