Project Options - Multi-Channel

Old Content - visit altium.com/documentation

Modified by Admin on Nov 6, 2013

The Multi-Channel tab of the Project Options dialog.

Summary

The Multi-Channel tab of the Project Options dialog enables you to specify the room and component designator naming formats, with respect to multi-channel designs.

Access

Click Multi-Channel tab in Printer Options dialog (Project » Project Options).

Options/Controls

Multi-channel design is the ability to reference the same sub-sheet in the project multiple times. This can be done by placing multiple sheet symbols that reference the same sub-sheet, or by including the Repeat keyword in the designator of a Sheet Symbol, to instantiate it multiple times.

The mapping from the single logical component on the schematic, to the multiple physical instances on the PCB is controlled by the multi-channel designator scheme defined in this dialog.

The tab is essentially divided into two areas - Room Naming and Component Naming.

Room Naming

Room Naming Style - There are alternative styles for naming rooms on a PCB document. Choose a naming style from the drop-down list and you can see the diagram below to see how the room naming styles are affected. Component designator formats are also affected if there is a $RoomName string in the designator.

The drop-down list to define the naming format you require for the rooms in your design. There are a total of five predefined styles available; two flat and three hierarchical.

As you select a style from the list, the image below is updated to reflect the naming convention that will appear in the design. The image gives an example of a 2x2 channel design. The larger cross-hatch regions represents the 2 upper level channels (or Banks) and the shaded regions within represent the lower level channels (with two sample components shown in each).

When the design is compiled, a room is created for each sheet in the design, including each bank and each lower-level channel. For the 2x2 channel design shown in the image, a total of 6 rooms will be created - one for each of the 2 Banks and one for each of the 4 lower level channels.

Level Separator for Paths - Specify the required character/symbol for separating the path information when using the hierarchical naming styles (those styles that include the path). The default is a _ (underline) level separator used for room naming styles when there are paths. Edit this field to change to another character as a separator.

Component Naming

Designator Format - There are alternate designator formats for naming components. Choose a format, or using the valid keywords, define your own format. Press F1 for a description of the available keywords.

The Room Naming Style is not relevant if the $RoomName string is not included in the Designator Format in the Component Naming drop-down list.

The drop down list defines the naming format you require for the component designators within your design. There are a total of eight predefined formats available - five flat and three that can be used in a hierarchical context:

$Component$ChannelAlpha
$Component_$ChannelPrefix$ChannelAlpha
$Component_$ChannelIndex
$Component_$ChannelPrefix$ChannelIndex
$ComponentPrefix_$ChannelIndex_$ComponentIndex
$Component_$RoomName
$RoomName_$Component
$ComponentPrefix_$RoomName_$ComponentIndex

The top five formats are all flat in nature. They simply name each component designator in a linear progression, starting from the first channel, thus avoiding duplication of designators.

The bottom three formats incorporate the room name into the overall designator for a component. If the room naming style chosen is one of the two possible flat styles, then the style for the component designator will also ultimately be flat in nature. However, if a hierarchical style has been chosen for room naming, (which incorporates the path information), then the component designator will also be hierarchical in nature.

You can also define your own component designator format, by typing directly inside the Designator Format field. The following keywords can be used when constructing the format string:

- $RoomName - this is the name of the associated room, as determined by the style chosen in the Room Naming Style field.
- $Component- this is the component logical designator.
- $ComponentPrefix- this is the component logical designator prefix (e.g. U for U1).
- $ComponentIndex- this is the component logical designator index (e.g. 1 for U1).
- $ChannelPrefix- this is the logical sheet symbol designator.
- $ChannelIndex- this is the channel index.
- $ChannelAlpha- this is the channel index expressed as a character.

To illustrate the difference between the flat and (possible) hierarchical designator formats, consider a 3x8 channel design. If a flat designator format is chosen, then the $ChannelIndex (or $ChannelAlpha) section of the string will vary in value from 1 to 24 (or A to X). If a designator format is chosen that contains the $RoomName keyword, and the Room Naming Styleis hierarchical, then the value will vary from 1 to 8 (A to H), for each of the three higher level channels (or banks).

Notes

There is no restriction on the entry used for the level separator, although to retain visual clarity, it is advisable to keep it to a single non-alphanumeric character.

The alpha indexing for a channel is only really useful if your design contains less than 26 channels in total, or if you are using a designator format that is hierarchical in nature.

You must recompile your project in order for any changes made to room and/or component designator formats, to take effect.

Hierarchical room names are formed by concatenating all channelized sheet symbol designators (ChannelPrefix + ChannelIndex) in the relevant channel path hierarchy.