My Hobbies - Circad Course - Lesson 10
Wiring with Bus and Joint elements

Parabola

Barra Colore


When you have a complex electric scheme, with many connection lines, is useful to use one or more bus to connect the components. To place a bus use PR, placing the line just you need. The bus, like a pipe, only transports signal lines, so it doesn't connect any component. To have a signal transported by a bus is necessary that a signal line ends (or starts, it's the same!) on the bus. Every bus line must be identified by a name different from the other signal lines carried by the bus.

The bus signal lines have a name, that must selected with PN, clicking over the track and entering its name (attention to the already used names).

For example, in TUTOR1.SCH you can try to remove, with DL, the wirings of D1, rotating it with GC+R and placing near it one little bus. Now, with PL or PW connect two signal tracks at the bus. The tracks must be called, with PN, QC and R2. Now, make the same thing for the R2 and Q1 pins (now not connected) calling the tracks, respectively, R2 and QC.

To check new wirings, use NS over one of the new tracks. Circad hilights all the circuit points connected to the selected signal.

With PS you can place a single signal port, using the signal name you wish. This kind of component is very useful to wire components far one from the other. The option is also useful in case of file splitted schematics: all the signal ports with the same name will be linked togheter, also if they exist on different .SCH files, due to their definitions, stored in the netlist of every schematic file. When the netlists will be imported in the pcb file all the signals with the same name will be wired togheter.

You can place many signal ports with the same name, so they will be electrically wired togheter. Always use NS to check the real electrical circuit connections.

A signal line can be transported by a bus simply placing an extemity of it over the bus. With PB you can do the same thing, but in a very professional mode, using 45° bus ports. These ports came with its silk name and must be connected with schematic signal lines to other schematic elements. The signal port extremity, below the port name, is wired to the user specified signal. You can verify this thing with the command NS.

There are another mode to link schematic circuit components to pcb elements: using joint. These are schematic components that the user can assigns at one specific pin of every pcb component. These elements are very useful, for example in case of big pcb connector, that cannot be drawn in a schematic file.

In fact, because pcb components have many different footprints, it's hard to draw for every pcb connector, its schematic equivalent shape.

The joint is a schematic component, only maded by a single pad and, optionally, by some silk elements (the one I use is maded by a pad and a little external circle silk). To make a joint type component, for example in the COMP_SCH.LIB library file, follow the Lesson 5 steps to make a schematic component, using "Pattern" = JP, "Ref ID" = JP?-?. The other fields must be left blank.

To use a joint place it with PC. In the "PCB Pattern" field insert the pcb component type that must be wired to the joint, then wire the joint to a specific signal line. In this example the pcb component is MOR2, a two pad connector. The specific pcb component pin that will be wired to the joint must be indicated in the "Ref ID" field, after the joint group number, with a minus sign followed by the pcb component pin number.

In the image above you can see that the joints connected to the same pcb component have the same number, followed by the pcb component pin number. All the same group joints must be assigned to the same pcb component. To better understand how joints works, you can download the file PicProgr.zip (17 Kb .zip) that contains the PICPROG.SCH file, where I've token the example above.



1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 11




Indice Index Storia History Curriculum Curriculum Pensieri Thoughts Cittą Cities Hobby Hobbies Link Links Novitą News
Scrivetemi Write me Guestbook!