要将符号摆放到原理图中，可以使用图标 或者快捷键 A 。 出现选择符号对话框，让您选择要添加的符号。 符号按符号库分组。

默认情况下，仅显示符号/库名称和描述列。 可以通过右键单击列标题并选择“选择列”来添加其他列。

The Choose Symbol dialog filters symbols by name, keywords, description, and all additional symbol fields according to what you type into the search field. You can choose to sort search results alphabetically or by best match by clicking on the button.

有一些高级筛选器可用：

如果符号指定了一个默认的封装，这个封装将在右下方预览。如果符号包括封装过滤器，可以在右边的封装下拉菜单中选择满足封装过滤器的备用封装。

选择一个要放置的符号后，该符号将被吸附在光标上。 左键点击原理图中所需要摆放的位置，将符号放入原理图中。在将符号放入原理图之前，可以通过快捷键或右键菜单来旋转、镜像或编辑它的字段。这些操作也可以在放置后进行。

如果 放置重复副本 选项被选中，在放置一个符号后 KiCad 将开始放置该符号的另一个副本。这个过程一直持续到用户按下 Esc。

对于有多个单元的符号，如果 放置所有单元 选项被选中，在放置符号后 KiCad 将开始放置该符号中的下一个单元。 这将持续到最后一个单元被放置或用户按下 Esc。

电源符号是代表与电源网络连接的符号。 这些符号被分组在 power 库中，所以可以使用符号选择器来放置。 然而，由于电源的放置很频繁， 工具是可用的。这个工具使用方法类似，只是搜索是直接在 power 库和其他包含电源符号的库中进行。

符号可以用移动（M）或拖动（G）工具移动。这些工具将作用于选定的符号，如果没有选定符号，则作用于光标下的符号。

移动 工具移动符号本身，而不保持与符号引脚的导线连接。

拖动 工具在移动符号时不会破坏其引脚的导线连接，因此也会移动连接的导线。

你也可以用鼠标点击并拖动符号，这取决于偏好设置中 鼠标和触摸板 部分的 左键拖动手势 设置。

符号也可以旋转（R）或在X（X）或Y（Y）方向上进行镜像。

符号的字段可以在符号的属性窗口中进行编辑。用快捷键 E 或通过双击符号来打开符号属性窗口。

The Symbol Properties window displays all the fields of a symbol in a table. New fields can be added, and existing fields can be deleted, edited, reordered, moved, or resized. Fields can be arbitrarily named, but names beginning with ki_, e.g. ki_description, are reserved by KiCad and should not be used for user fields.

每个字段的名称和值可以是可见的或隐藏的，并且有几个格式化选项：水平和垂直对齐、方向、位置、字体、文本颜色、文本大小和黑体/斜体。字段的自动放置也可以在每个字段的基础上启用。显示位置始终针对正常显示的符号（无旋转或镜像）指示，并且与符号的锚点相关。

The Update Symbol from Library…​ button is used to update the schematic’s copy of the symbol to match the copy in the library. The Change Symbol…​ button is used to swap the current symbol to a different symbol in the library. These functions are described later.

Edit Symbol…​ opens the Symbol Editor to edit the copy of the symbol in the schematic. Note that the original symbol in the library will not be modified. The Edit Library Symbol…​ button opens the Symbol Editor to edit the original symbol in the library. In this case, the symbol in the schematic will not be modified until the user clicks the Update Symbol from Library…​ button.

符号有几个属性，它们会影响 KiCad 其他部分对符号的处理方式。

Exclude from simulation prevents the symbol from being included in SPICE simulations.

Exclude from bill of materials prevents the component from being included in BOM exports.

Exclude from board means that the symbol is schematic-only, and a corresponding footprint will not be added to the PCB.

Do not populate means that the component should not be attached to the PCB, although a corresponding footprint should still be added to the board. DNP symbols appear desaturated and with a red "X" over them in the schematic, as shown below.

When a symbol is added to the schematic, KiCad embeds a copy of the library symbol in the schematic so that the schematic is independent of the system libraries. Symbols that have been added to the schematic are not automatically updated when the library changes. Library symbol changes are manually synced to the schematic so that the schematic does not change unexpectedly.

To update symbols in the schematic to match the corresponding library symbol, use Tools → Update Symbols from Library…​, or right click a symbol and select Update Symbol…​. You can also access the tool from the symbol properties dialog.

The top of the dialog has options to choose which symbols will be updated. You can update all symbols in the schematic, update only the selected symbols, or update only the symbols that match a specific reference designator, value, or library identifier. The reference designator and value fields support wildcards: * matches any number of any characters, including none, and ? matches any single character.

The middle of the dialog has options to control what parts of the symbol will be updated. You can select specific fields to update or not update, which properties of the fields to update (text, visibility, size and style, and position), and how to handle fields that are missing or empty in the library symbol. You can also choose whether to update symbol attributes, such as do not populate and exclude from simulation / bill of materials / board.

The bottom of the dialog displays messages describing the update actions that have been performed.

To change an existing symbol to a different symbol, use Edit → Change Symbols…​, or right click an existing symbol and select Change Symbol…​. This dialog is also accessible from the symbol properties dialog.

The options for the Change Symbols dialog are very similar to the Update Symbols from Library dialog.

Another way to swap existing symbols for new ones is to use Tools → Edit Symbol Library Links…​. This dialog contains a table of every symbol in the design, grouped by current library symbol. By choosing a new symbol in the New Library Reference column, you can make all instances of the existing symbol instead point to the new symbol. If the Update symbol fields from new library option is used, the contents of the existing symbols' fields will be updated to match the new symbols' fields.

The Map Orphans button attempts to automatically remap orphaned symbols to symbols with the same name in an active library. For example, if there is a symbol with the current library reference mylib:symbol123, but the mylib library cannot be found, the Map Orphans button will attempt to find a symbol named symbol123 in any of the libraries that are present. This button is only enabled if orphaned symbols are present in the schematic (see the legacy schematics section).

This dialog is primarily useful for managing symbols that appear in multiple libraries, when you want to switch from one library to another. For example, if a schematic uses symbols that are in both a global library and a project-specific library, the Symbol Library References dialog could be used to switch between using the global symbols or the equivalent project-specific symbols. It does not have features for fine-grained control of how fields are updated; for that, use the Change Symbols dialog.

When a symbol in a schematic diverges from the corresponding symbol in the original symbol library, you can use the Compare Symbol with Library tool to inspect the differences between the two versions of the symbol. Run the tool using Inspect → Compare Symbol With Library.

The Summary tab shows the name of the symbol, including its library and schematic reference designator, and provides a list of the differences between the schematic and library versions of the symbol.

The Visual tab shows a visual comparison of the schematic and library versions of the symbol. This can be used as a visual diff tool.

By default, the comparison displays both versions of the symbol superimposed on each other. To see the changes more easily, you can drag the slider at the bottom of the tab to the right to emphasize the library version of the symbol in the superimposed view (making the schematic version of the symbol more transparent) or drag it to the left to emphasize the schematic version (making the library version more transparent). At the far right and left ends of the slider, the schematic and library versions of the symbol, respectively, are fully hidden. It may be helpful to drag the slider back and forth to see the changes more clearly.

The screenshot above shows a visual comparison with the schematic version of the symbol deemphasized. You can see a partially transparent pin 5 (from the schematic version of the symbol) is in a different location than the fully opaque pin 5 (from the library symbol). This indicates that the pin was moved in either the schematic or library version of the symbol.

符号字段表允许你在电子表格界面中查看和修改所有符号的字段值。你可以用 按钮打开符号字段表。

Cells are navigated with the arrow keys, or with Tab / Shift+Tab to move right / left and Enter to move down, respectively.

通过点击和拖动可以选择一个单元格范围。选定的整个单元格范围可以通过（Ctrl+C）或（Ctrl+V）进行复制或粘贴。从表中复制单元格的对于创建 BOM 非常有用。下面将介绍复制和粘贴单元格的更多细节。

Any symbol field can be shown or hidden using the Show checkboxes on the left or by right-clicking on the header of the table. New symbol fields can be added using the button; a field with that name will be added to every symbol. Each field can have its own label, which doesn’t have to be the same as the field name, and is used as the column header. Fields can be renamed with the button or deleted with the button.

Similar symbols can optionally be grouped by any symbol field using the Group By checkboxes. Symbols are grouped into a single row in the table if all of their Group By fields are identical. The grouped row can be expanded to show the individual symbols by clicking the arrow at the left of the row. The Group Symbols checkbox enables or disables symbol grouping, and the button recalculates groupings.

预置可用于配置字段列表。预置可存储显示的字段、用于分组的字段以及列顺序。 您可以创建并保存自己的预置，也可以使用多个默认预置之一。 自定义预置可以在此对话框或 《原理图设置，原理图设置》 对话框中删除。

Symbols can be filtered by reference designator using the Filter textbox at the top. The filter supports wildcards: * matches any number of any characters, including none, and ? matches any single character. You can also change the display scope, showing only symbols in the current sheet, the current sheet and all of its subsheets, or the entire project. Symbols with the DNP (do not populate) attribute set can be optionally excluded by checking the Exclude DNP box.

You can cross-probe from this dialog by selecting a row in the table. Depending on the Cross-probe action setting at the bottom of the dialog, this can highlight the corresponding symbol in the schematic, select the corresponding symbol in the schematic, or do nothing. The selection action can also select the symbol’s footprint in the board editor, depending on the PCB Editor cross-probing settings.

The Symbol Fields Table is also a bill of materials tool. You can use the Export button to save the symbol fields to an external file. The fields are exported to the BOM exactly as they are currently shown in the spreadsheet view. File format settings are configured in the Export tab. For more information about exporting a BOM, see the BOM tool documentation.

启用自动批注后，符号被添加到原理图中时将被自动批注。你可以在 偏好设置 中 原理图编辑器 → 批注选项 窗格中选中 自动批注符号 复选框来启用自动批注。自动批注也可以通过左侧工具栏的 按钮进行切换。

当同时添加多个符号时，它们会根据 顺序 设置进行批注，按 X 或 Y 位置排序。

编号 选项为新的位号设置起始编号。 可以是最小的可用数字，也可以是基于原理图页码的数字。

关于批注选项的更多信息，请参见批注工具的文档。

批注工具会自动为原理图中的符号指定位号。要启动批注工具，请点击顶部工具栏上的 按钮。

该工具提供了几个选项来控制符号的批注方式。

Scope: Selects whether annotation is applied to the entire schematic, to only the current sheet, or to only the selected symbols. If the Recurse into subsheets option is selected, symbols in subsheets of the selected scope will be reannotated; otherwise symbols in subsheets will not be reannotated. For example, if Recurse into subsheets and Selection only selected, symbols in any selected subsheets will be reannotated.

Options: Selects whether annotation should apply to all symbols and reset *existing reference designators, or apply only to unannotated symbols.

Order: Chooses the direction of numbering. If symbols are sorted by X position, all symbols on the left side of a schematic sheet will be lower numbered than symbols on the right side of the sheet. If symbols are sorted by Y position, all symbols on the top of a sheet will be lower numbered than symbols at the bottom of the sheet.

Numbering: Selects the starting point for numbering reference designators. The lowest unused number above the starting point is picked for each reference designator. The starting point can be an arbitrary number (typically zero), or it can be the sheet number multiplied by 100 or 1000 so that each part’s reference designator corresponds to the schematic page it is on.

清除批注 按钮可以清除所选范围内的所有位号。

批注信息可以用底部的复选框进行过滤，或用 保存…​ 按钮保存到报告中。

导线用于在两点之间直接建立电气连接。 要建立连接，必须将一段导线的末端与另一段导线或一个引脚相连。只有导线的末端才能建立连接；如果一根导线穿过另一根导线的中间，不会建立连接。

未连接的导线端有一个小方块，表示连接点。 当连接到导线端时，这个方块就会消失。未连接的引脚有一个圆圈，连接完成时时也会消失。

标签是用来给导线和引脚分配网络名称的。具有相同网络名称的导线被认为是连接在一起的，所以标签可以用来进行连接，而不需要直接画线连接。

A net can only have one name. If two different labels are placed on the same net, an ERC violation will be generated. Only one of the net names will be used in the netlist. The final net name is determined according to the rules described below.

有三种类型的标签，每种都有不同的连接范围。

总线是一种在原理图中分组相关信号的方法，以简化复杂的设计。 总线可以像导线一样用总线工具画出来 ，并像信号线一样用标签命名。

在下面的原理图中，许多引脚都连接到总线上，也就是中间的蓝色粗线。

Power symbols are symbols that are conventionally used to represent a connection to a power net, such as VCC or GND. Power symbols are virtual: they do not represent a physical component on the PCB.

In addition to being a visual indicator that the attached net is a power rail, power symbols make global connections: two power symbols with the Value connect to each other anywhere in the schematic, regardless of sheet. The power symbol’s Value field determines the name of the attached net.

在下图中，电源符号用于将电容器的正负极分别连接到 VCC 和 GND 网络上。

In the KiCad standard library, power symbols are found in the power library, but power symbols can be created in any library. Creating custom power symbols is described in the symbol editor documentation. Instead of making a new symbol, you can also modify an existing power symbol in the schematic: changing its Value field will change the net the power symbol connects to.

原理图中的每个网络都被分配了一个名称，无论这个名称是由用户指定还是由 KiCad 自动生成。

当多个标签附加到同一个网时，最终的网络名将按以下顺序确定，从最高优先级到最低：

如果一个网络有多个同一类型的标签，则按字母顺序排序，使用第一个。

如果一个网络经过层次的多张原理图，它的名字将取决于层次结构中优先级最高的标签。通常，局部标签优先级高于层次标签。

如果以上标签类型都没有添加到网络中，那么网络的名称将根据连接的符号引脚自动生成。

上面的截图中可以看到两个 PWR_FLAG 符号。它们向 ERC 表明，两个电源网络 VCC 和 GND 实际上连接到一个电源上，虽然没有明确的电源输出（如电压调节器输出）连接到以上两个网络。

如果没有这两个标志，ERC 工具会诊断出：错误：输入电源引脚没有被任何输出电源引脚驱动。

PWR_FLAG 符号可以在 power 符号库中找到。将任何电源输出引脚连接到网络上，可以达到同样的效果。

No-connection flags () are used to indicate that a pin is intentionally unconnected. These flags prevent "unconnected pin" ERC warnings for pins that are intentionally unconnected. Also, while symbol pins that are stacked on top of each other are normally connected to the same net, if a no-connection flag is added to the stacked pins they will instead be connected to separate nets.

Note that no-connection flags are distinct from the "unconnected" symbol pin type, although they both prevent "unconnected pin" ERC warnings on the pin in question and prevent stacked pins from connecting to each other.

When the power pins of a symbol are visible, they must be connected, as with any other signal. However, symbols are sometimes drawn with hidden power input pins, which are connected implicitly. KiCad automatically connects invisible pins with type Power Input to a global net with the same name as the pin. For example, if a symbol has a hidden power input pin named VCC, this pin will be globally connected to the VCC net on all sheets. This kind of implicit connection is not recommended in new designs.

Net classes are managed in the Net Classes panel of the Schematic Setup dialog.

The top pane lists the net classes that exist in the design. The Default net class always exists, and you can add additional net classes with the button or remove the selected net class with the button.

Net classes can be moved up and down in priority order with the and buttons. Note that the Default net class will always be the lowest priority net class and can therefore not be moved.

Each net class can have unique graphic properties that determine how wires of that net class are displayed in the schematic. Wire and bus thicknesses, color, and line style (solid, dashed, dotted, etc.) can all be adjusted. Setting the color to transparent will use the theme’s default wire/bus color for the net class, which is configurable in Preferences.

You can also set board design rules for each net class, although the DRC fields are hidden by default. Right click the header row to show or hide additional columns. For more information about setting net class design rules, see the PCB editor documentation.

All net class parameters for user-defined net classes are optional. However, all properties belonging to the Default net class must be set. When a net has more than one net class assigned, the appropriate value for graphic properties or board design rules is taken from the highest priority assigned net class with the relevant value set. If only one net class is assigned which contains missing properties, any missing values will be taken from the Default net class.

The bottom pane lists pattern-based net class assignments. Each row has a net name pattern and a net class; nets with names that match the pattern are assigned to the specified net class. If a net matches multiple patterns, the first match is used. Pattern-based net class assignments are dynamic: when a new net is added that matches an existing pattern, it will be assigned to the associated net class automatically. Net patterns can use both wildcards (* to match any number of any characters, including none, and ? to match any character) and regular expressions. The nets that match the selected pattern are displayed to the right of the pattern list.

例如, net* 模式匹配名为 net , net1, network, 和任何其他以 net 开头的网络名称的网络。 因为 * 在正则表达式中的含义略有不同（* 匹配零个或多个前面的字符）, net* 模式也匹配名为 ne 的网络。

Use the button to add a net class assignment pattern or the button to remove a pattern.

Instead of adding net class patterns in the Schematic Setup dialog, you can directly create net class patterns from the schematic canvas. Right click a net and select Assign Netclass…​ to bring up the Add Netclass Assignment dialog. The net class pattern is pre-filled with the name of the selected net, but the pattern can be changed if desired. All nets matching the pattern are displayed in the dialog. This method can only be used on nets with an assigned name.

As an alternative to pattern-based net class assignment, net classes can be graphically assigned to nets in the schematic using either directive labels, net labels, or rule areas. Net classes must be created in Schematic Setup before they can be assigned graphically.

In the image below, a directive label is used to assign signals to the 50R net class.

Directive labels are added with the button in the right toolbar. They behave like labels, except that they cannot be used to name a net. The attached net is assigned a net class according to the value of the directive’s Net Class field. The Net Class field presents a dropdown list of all the net classes in the design.

如果一个标识符被附加到一个总线上，总线上的所有成员都被分配到指定的网络类。

In addition to the associated net class, you can edit the directive’s shape (dot, circle, diamond, or rectangle), orientation, pin length, and color in the directive’s properties.

Net labels can also be used to assign net classes to nets by adding a Net Class field to the label.

The Rule Area tool can be used to draw a shape to which net class directives can be attached. Any wire, bus, label, or symbol pin which crosses or is inside the rule area will be assigned the net class of a net class directive attached to the rule area border. An example is shown in the image below; all wires passing through the rule area will be assigned the RAM_ADDR net class.

You can show or hide directive labels in the schematic using the View → Show Directive Labels option.

Two kinds of text can be added to schematics, which are referred to as text () and text boxes (). Both are added using their respective buttons in the right toolbar. Text boxes are similar to regular text except that they have an optional border and they automatically reflow text within that border.

这两种文本项目都支持多行文本和基本的格式设置功能，文本框还可以将文本换行以适应文本框外框，并有额外的格式选项。所有的文本都有可调整的字体、颜色、大小、黑体和斜体，左右对齐，以及垂直和水平方向。文本框还支持水平居中，垂直对齐选项，以及彩色边框和填充。

Graphic rectangles (), circles (), arcs (), and lines () can all be added using their respective buttons in the right toolbar.

线宽、颜色和样式（实线、虚线或点线）可以在每个图形（E）的属性对话框中进行配置。矩形、圆形和弧形也可以设置填充颜色并去除其轮廓线。

将形状的线宽设置为 0，则使用原理图的默认线宽，该线宽可在 <schematic-setup,原理图设置>> 中配置。虚线的间距也可以在那里配置。移除线条或填充物的颜色将会使用颜色主题的图形颜色，这可以在 偏好设置 中配置。

与导线一样，图形的线条服从线条的绘制模式设置（90 度，45 度，或自由角度），可以用左侧工具栏的切换按钮来设置 (, , and )。 Shift+Space 循环切换这些模式。

与 PCB 布线一样 ，/ 快捷键切换线条模式。

位图图像可以通过 按钮添加到原理图中。原理图中的图像可以被移动和缩放。属性对话框允许设置位置和比例，以及将图像转换为灰度。

文本和图形的属性可以通过 编辑文本和图形属性 对话框（工具 → 编辑文本和图形属性…​）进行批量编辑。该工具还可以修改导线和总线的视觉属性。

标题栏是用页面设置工具（）编辑的。

可以编辑标题栏中的每个字段，以及纸张大小和方向。 如果为某个字段选中了 导出到其他原理图页 选项，则该字段将在所有原理图页的标题栏中更新，而不仅仅是当前原理图页。

你可以用 发布日期 旁的左箭头按钮将日期设置为今天或其他任何日期，但原理图中的日期不会自动更新。

也可以选择一个原理图模板文件。

原理图页码（页面X/Y）会自动更新，也可以用 编辑 → 编辑原理图页码…​ 手动设置。

You can quickly add wires, labels, or no-connection markers to a selection of pins using the Pin Helpers tools in the right-click context menu. This can help you quickly break out unconnected pins from a symbol or hierarchical sheet. By selecting Pin Helpers → Wire, the wire tool will begin drawing a wire from all selected pins at once. If you select No Connect, no-connection markers will be added to the end of each selected pin. And if you choose Net Label, Hierarchical Label, or Global Label, a label of the respective type will be placed at the end of each selected pin. Each label’s name will be set to the corresponding pin name. The new labels will remain selected, so you can easily move them away from the symbol using M or G, depending on whether you wish to maintain a wired connection between the pins and the labels.

Existing labels and text objects can be changed to another type of label or text by right clicking the object(s) and selecting the target object type from the Change To submenu. The allowed types for source and target objects are local labels, global labels, hierarchical labels, directive labels, text objects, and text boxes. The value of the original object is preserved in the resulting object: when a text object is converted to a label, the label’s value (net name) will be the original text, and vice versa.

You can swap the position of two selected objects using the Swap command (S; also available in the right-click context menu). This works on symbols, labels, and graphical items. The first object is assigned the location and rotation of the second object, and vice versa. If there are more than two objects selected, the locations are cycled: the last object gets the position of the first object, the first object gets the location of the second, and so on.

格式化面板包含符号、文本、标签、图形和导线的外观设置。

Symbol unit notation sets how each unit of a multi-unit symbol is referred to in its reference designator. By default, a different letter for each unit is appended to the reference designator with no separator, for example U1B for the second unit of symbol U1, but this can be changed. Numbers can be used instead of letters, and various separators can be used between the symbol designator and the unit identifier (., -, _, or none).

Default text size sets the default text height used by the text, text box, and label tools. Overbar offset ratio controls the vertical spacing between text and an overbar (~{}) over that text, as a ratio of the text height. Label offset ratio controls the vertical spacing between a local label’s text and the attached wire, relative to the label’s text size. This also affects the spacing between symbol pins and their pin number. Global label margin ratio defines the size of the box around a global label, relative to the global label’s text size. Increasing the margin may be useful to avoid overlapping text with overbars (~{}) or letters with descenders, but this may cause closely packed global labels to overlap with each other.

Default line width sets the default line width for symbol graphics, if the symbol does not override the default line width. Pin symbol size scales symbol pin graphic style annotations, such as the bubble on an inverted pin.

Junction dot size sets the schematic’s default wire junction dot size. The default size can be overridden by editing an individual junction dot’s properties. Connection width specifies the grid size used for the Symbol pin or wire end off connection grid ERC check. Schematics typically use a 50 mil grid for electrical connections, so this should usually remain set at 50 mils.

The Operating Point Overlay settings configure how operating point simulation results are displayed on the schematic canvas. The significant digits settings control the number of significant digits printed on voltage and current overlays. The range settings control the units used to display voltage and current measurements.

Show inter-sheet references enables or disables the display of inter-sheet references, which are a list of page numbers next to a global labels that link to other places in the schematic where the same global label appears. Show own page reference controls whether the current page is included in the list of page numbers. Standard and abbreviated determine whether to display the complete list of page numbers or only the first and last page numbers. The prefix and suffix fields add optional characters before and after the list of page numbers. In the image of an inter-sheet reference below, a prefix and suffix of [ and ], respectively, have been added.

虚线外观在格式部分中控制。 虚线长度 控制破折号的长度，而 间隙长度 控制破折号和点之间的间距。 破折号和间隙长度是相对于线宽的：间隙长度为 2 则表示线宽的两倍。

字段名称模板是空的符号字段，会自动添加到原理图中的所有符号。 当原理图中的每个符号都需要在符号中定义的默认字段之外的其他字段时，这可能很有用，例如制造商部件号的字段。

模板字段可以设置为可见或不可见，也可以设置为URL 字段。

在原理图设置中定义的字段名称模板仅适用于当前项目。 字段名称模板也可以在偏好设置中定义，它适用于在您的计算机上编辑的所有项目。

BOM presets are saved configurations for the Symbol Fields Table and BOM export tool. There are two types of presets. BOM presets configure which fields are displayed in the symbol fields table, which order they are displayed in, and how they are used to group symbols. These fields are also directly used in the BOM output. BOM formatting presets configure the output BOM file format, including which separator characters are used to separate fields. Both types of presets are created in the Symbol Fields Table, but can are listed and can be deleted here.

违规严重性 面板可让您配置应将哪些类型的 ERC 消息报告为错误、警告或忽略。

引脚冲突映射 允许您配置连接规则，以根据相互连接的引脚类型定义错误和警告的电气条件。 例如，默认情况下，当输出引脚连接到另一个输出引脚时会产生错误。

这些面板在 [ERC - 配置，ERC 章节] 中有更详细的解释。

The Net Classes panel allows you to manage net classes for the project and assign nets to net classes with patterns. Managing net classes in this panel is equivalent to managing them in the Board Setup dialog. Nets can also be assigned to net classes in the schematic using graphical assignments with net class directives or net labels.

Pattern-based net class assigment is explained in more detail in the net classes section.

总线别名定义 面板允许您创建总线别名，这是总线中信号组的名称。 有关总线别名的更多信息，请参阅 [总线-别名，总线别名文档]。

文本替换变量可以在文本变量部分创建。 这些变量允许您用变量名替换任何文本字符串。 这种替换发生在变量名称在 ${VARIABLENAME} 的变量替换语法中使用的任何地方。

例如，您可以创建一个名为 VERSION 的变量并将文本替换设置为“1.0”。 现在，在 PCB 上的任何文本对象中，您可以输入 ${VERSION}，KiCad 将其替换为 1.0。 如果将文本替换更改为 2.0，则包含 ${VERSION} 的每个文本对象都将自动更新。 您还可以混合使用常规文本和变量。 例如，您可以使用文本 Version: ${VERSION} 创建一个文本对象，它将被替换为 Version: 1.0。

文本变量也可以在 电路板设置中创建。 文本变量是项目范围的； 在原理图编辑器中创建的变量在电路板编辑器中也可用，反之亦然。

还有一些内置系统文本变量。

Modern versions of KiCad can open schematics created in versions prior to KiCad 6.0, but the cache library file (<projectname>-cache.lib) must be present to load the schematic correctly.

Since version 6.0, KiCad stores all symbols used in a project in the schematic. This means that you can open a schematic made in KiCad 6.0 or later on any computer, even if the libraries used in the project are not installed or have changed. Modern KiCad schematic files use the .kicad_sch extension.

Prior to version 6.0, KiCad did not store symbols in the schematic. Instead, KiCad stored references to the symbols and their libraries. It also stored a copy of every symbol used by the project in a separate cache library file (<projectname>-cache.lib). As long as the cache library was included with the project, the project could be distributed without the system library files, because KiCad could load any needed symbols from the cache library as a fallback if the libraries referenced in the schematic were missing. Legacy KiCad schematic files use the .sch extension.

When you open a legacy schematic, KiCad will look in the cache library to find all of the symbols used in the schematic in the cache library. When you save the legacy schematic, KiCad will save it as a new file in the modern schematic format (.kicad_sch), with the necessary symbols embedded in the schematic itself. The original legacy schematic and the cache library will remain, unmodified, but they are no longer necessary once the schematic has been saved in the modern format.

When you open a legacy schematic, KiCad may display the Project Rescue Helper dialog. This means that one or more symbols in the cache library do not match the corresponding symbol in the external library. The dialog helps you "rescue" symbols from the cache library into your schematic, if desired. You can also open the rescue dialog at any time using Tools → Rescue Symbols…​. The cache library file must be present in order to use the rescue tool.

The rescue dialog lists all symbols that don’t match between the cache library and the external symbol library. The discrepancy can be because:

For each symbol in the list, selecting the symbol displays the reference designator and value for each instance of the symbol, and shows a visual preview of the symbol. If a corresponding symbol exists in the system symbol library, the dialog shows both copies of the symbol for comparison. If the symbol only exists in the cache library, the dialog only shows the cached symbol.

In this example, the project originally used a diode with the cathode facing left, but the library now contains one with the cathode facing right. This change would break the design, so it would be important to use the cached symbol as the original designer intended.

Pressing Rescue Symbols here will cause the selected symbols from the cache library to be saved into a special rescue library (<projectname>-rescue.kicad_sym). The corresponding symbols in the schematic will be updated to use the newly rescued symbols. Any unselected symbols will not be rescued, but their symbol linkage can be updated in the schematic later.

Alternatively, pressing Skip Symbol Rescue will exit the dialog without rescuing any symbols. KiCad will use the versions of the symbols found in the external libraries. You can run the rescue function again with Tools → Rescue Symbols…​, or manually edit symbol linkage in the symbol’s properties.

If you would prefer not to see this dialog, you can press Never Show Again. This has the same effect as pressing Skip Symbol Rescue for the current schematic and all future schematics.

If a symbol in a legacy schematic cannot be found in either the cache library or the external library, KiCad cannot rescue that symbol. A placeholder symbol is inserted into the schematic in its place, as shown below.

You can attempt to remap these orphaned symbols using the Change Symbols or Edit Symbol Library Links dialogs, but either option may require manual corrections to the schematic. These tools are explained in more detail in the Updating and exchanging symbols section.

Modern versions of KiCad can open schematics created in versions prior to KiCad 5.0, but you will need to go through a symbol remapping process to open the schematic without losing symbol information.

Since version 5.0, KiCad schematics refer to specific symbols using both the symbol and library name. Even if multiple libraries each contain a symbol with the same name, the designer’s intended symbol is unambiguously specified.

Prior to version 5.0, KiCad schematics stored only the symbol name, not the library name. Symbols in the schematic were indirectly mapped back to the original library by searching through the project’s library list for a matching symbol. When you open a pre-5.0 schematic, KiCad will attempt to automatically "remap" the symbols so that each bare symbol name is replaced with a fully-specified symbol library and symbol name pair. The original schematics will be backed up in a rescue-backup folder.

You can skip the automatic remapping, but you will need to remap the symbols yourself using the Change Symbols dialog. You can also re-run the Remap Symbols tool using Tools → Remap Legacy Library Symbols…​.