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--- geda:gschem_symbol_creation [2012/11/12 13:00]
vzh Fix header
+++ geda:gschem_symbol_creation [2015/12/02 05:16] (current)
vzh Add link to generators page
@@ Line 1: / Line 1: @@
+//Translations of this guide are also available in the following languages:// [[gschem_symbol_creation.ru|Русский]]
 ====== gEDA/gaf Symbol Creation ======
@@ Line 5: / Line 7: @@
 ===== Overview =====
-This document describes the creation of component symbols, including style conventions, and hints/tips and things to look out for when drawing symbols for the gEDA/gaf system.
+This document describes the manual creation of component symbols,
+including style conventions, and hints/tips and things to look out
+for when drawing symbols for the gEDA/gaf system.
+For automatic symbol creation or conversion from other formats
+please see the [[gschem symbol generators]] page.
 ===== Component Symbol Creation =====
@@ Line 66: / Line 72: @@
   - A ''graphical=1'' attribute should exist somewhere in a symbol which is purely graphical (such as a title block or //decon// symbol). Symbols which have this attribute have no electrical or circuit significance. Don't forget to set ''device=none'' per the previous step.
   - A ''description=TEXT'' attribute should exist somewhere in the symbol. The ''TEXT'' value should provide a one line description of the symbol.
-  - A ''footprint=PACKAGENAME'' attribute should exist somewhere in the symbol which might be used with a pcb netlister. ''PACKAGENAME'' is a pcb footprint or package type like DIP14 or DIP40. Please see the footprint naming conventions page for further detail. If you are using gEDA / PCB, also see the PCB documentation and gnetlist/docs/README.pcb for more info on this attribute and how it is used.
+  - A ''footprint=PACKAGENAME'' attribute should exist somewhere in the symbol which might be used with a pcb netlister. ''PACKAGENAME'' is a pcb footprint or package type like DIP14 or DIP40. Please see the [[pcb_footprint_naming_conventions | footprint naming conventions]] page for further detail. If you are using gEDA / PCB, also see the [[http://pcb.geda-project.org/manual.html|PCB documentation]] and gnetlist/docs/README.pcb for more info on this attribute and how it is used.
   - A ''refdes='' attribute should be placed inside all non-graphical symbols. This attribute should default to ''U?'' for integrated circuits, and 'T?' for transistors. Make only the value visible and it will be promoted (attached to the outside of the symbol (so it can be edited)) when the symbol is placed in a schematic.
-  - A ''numslots='' attribute should be placed inside of all symbols, to prevent a warning. ''numslots=1'' works fine.
+  - A ''numslots='' attribute should be placed inside of all symbols, to prevent a warning when you will check your symbol by gsymcheck. ''numslots=1'' works fine.
 Now that those have been added, make the ''numslots'', ''footprint'', ''description'', ''graphical'' and ''device'' attributes invisible. Leave only the value of the ''refdes'' attribute visible, and place it somewhere at the top of your symbol.
@@ Line 74: / Line 80: @@
 ==== Finishing ====
   - Add a label to your symbol by selecting **Add**->**Text...** or pressing <key>a</key> <key>t</key>. Type out your label, and move it to the top of your symbol.
-  - Translate the symbol to the origin using **Edit**->**Symbol Translate...**
+  - Translate the symbol to the origin using **Edit**->**Symbol Translate...** or press <key>e</key> <key>t</key>.
-  - Select **Symbol Translate...** or the press equivalent hotkey.
   - Enter '0' into the entry field and press **OK**.
   - Save the symbol using **File**->**Save** or **File**->**Save As...**
-  - Place the symbol in one of the directories specified by the ''component-library'' keyword in the system-gafrc file. Once this is done, the symbol should be visible immediately and can be selected and placed with the **Add**->**Select Component...** menu item. On Debian, placing files in /usr/share/gEDA/sym/local/ works, but require permissions setup.
+  - Place the symbol in one of the directories specified as a symbol library in a suite configuration file  (one of the "gafrc" files).  For an explanation of how to set up symbol libraries, see the [[geda:gschem_ug:config|gEDA gschem User Guide]]. Once this is done, the symbol should be visible immediately and can be selected and placed with the **Add**->**Select Component...** menu item. On Debian, placing files in /usr/share/gEDA/sym/local/ works, but requires permissions setup.
 === Note ===
@@ Line 97: / Line 102: @@
   - All pins should have a ''pinnumber'' attribute attached to them. This is the number of the pin, on the package of the item you are drawing a symbol for. The pin number can be alphanumeric (i.e. like E or C).
   - All pins should have a ''pinlabel'' attribute attached to them. This attribute is the name or label of the pin (not the pin number). This attribute is also used when a symbol is used in a hierarchical schematic.
-  - All pins should have ''pintype'' attribute attached to them. This attribute describes the kind of a pin. Possible values are: ''in'', ''out'', ''io'', ''oc'', ''oe'', ''pas'', ''tp'', ''tri'', ''clk'', ''pwr''. Please see the [[master_attributes_list|Master Attribute Document]] for more info.
+  - All pins should have ''pintype'' attribute attached to them. This attribute describes the kind of a pin. Possible values are: ''in'', ''out'', ''io'', ''oc'', ''oe'', ''pas'', ''tp'', ''tri'', ''clk'', ''pwr''. Please see the [[master_attributes_list#pintype|Master Attribute Document]] for more info.
@@ Line 107: / Line 112: @@
   - A ''graphical=1'' attribute should exist somewhere in a symbol which is purely graphical (such as a title block or //decon// symbol). Symbols which have this attribute have no electrical or circuit significance. Don't forget to set ''device=none'' per the previous requirement.
   - A ''description=TEXT'' attribute should exist somewhere in the symbol. The ''TEXT'' value should provide a one line description of the symbol.
-  - A ''footprint=PACKAGENAME'' attribute should exist somewhere in the symbol which might be used with a pcb netlister. ''PACKAGENAME'' is a pcb footprint or package type like DIP14 or DIP40. Please see the [[pcb_footprint_naming_conventions | footprint naming conventions]] page for further detail. If you are using gEDA / PCB, also see the PCB documentation and gnetlist/docs/README.pcb for more info on this attribute and how it is used.
+  - A ''footprint=PACKAGENAME'' attribute should exist somewhere in the symbol which might be used with a pcb netlister. ''PACKAGENAME'' is a pcb footprint or package type like DIP14 or DIP40. Please see the [[pcb_footprint_naming_conventions | footprint naming conventions]] page for further detail. If you are using gEDA / PCB, also see the [[http://pcb.geda-project.org/manual.html|PCB documentation]] and gnetlist/docs/README.pcb for more info on this attribute and how it is used.
   - A ''refdes=U?'' attribute should be placed inside all non-graphical symbols. Make only the value visible and it will be promoted (attached to the outside of the symbol, so it can be edited) when the symbol is placed in a schematic.
   - The ''label='' and ''name='' attributes should not exist anywhere in the symbol. They are obsolete.
@@ Line 114: / Line 119: @@
 === Slotting ===
   - If a component has multiple slots in a package (such as a 7400 (NAND) which has 4 NANDs per package) then you need a ''numslots=#'' attribute. The ''#'' is the number of slots the device has. ''numslots='' should be exist somewhere in the symbol and made invisible. Additional slot related required attributes are described below.
-  - If a component has multiple slots in a physical package then you also need to include a ''slotdef=#:#,#,#...'' for every slot. The first ''#'' corresponds to the slot number. If a device has 4 slots then there should be ''slotdef=1:...'', ''slotdef=2:...'', ''slotdef=3:...'', and ''slotdef=4:...'', attributes existing somewhere in the symbol and made invisible. The subsequent ''#'' have a one-to-one correspondence to ''pinseq=#'' attributes and specify what corresponding ''pinnumber=#'' should be when that slot is set. See the attached 7400-1.sym as an example of how this should all work.
+  - If a component has multiple slots in a physical package then you also need to include a ''slotdef=#:#,#,#...'' for every slot. The first ''#'' corresponds to the slot number. If a device has 4 slots then there should be ''slotdef=1:...'', ''slotdef=2:...'', ''slotdef=3:...'', and ''slotdef=4:...'', attributes existing somewhere in the symbol and made invisible. The subsequent ''#'' have a one-to-one correspondence to ''pinseq=#'' attributes and specify what corresponding ''pinnumber=#'' should be when that slot is set. See the [[#Example|attached 7400-1.sym]] as an example of how this should all work.
   - It is recommended that all symbols which have slots have a ''slot=1'' attribute inside the symbol.
@@ Line 134: / Line 139: @@
 ==== Attributes ====
   * ''pinnumber'' attributes should be displayed as pin numbers for pins (not ''pinseq'') and should be 8 pt in size.
-  * Attached attributes should be yellow. The color is set automatically to yellow if the text item is attached.
+  * Attached attributes should be color number 5 (attributes | yellow). The color is set automatically to yellow if the text item is attached.
   * The only exception to this is ''pinlabel='' attributes, those should be color number 9 (text | green). If every text item within a symbol is yellow, the symbol looks too yellow.
   * Attributes can be attached to some part of the symbol. Toplevel attributes (like the ''device='' or ''net='' attributes) used to be required to be attached to something to be attributes, but now they just have to exist in the symbol file as ''name=value''.
   *  Expanding a bit on the last sentence, as long as the text item has the format ''name=value'', it is considered an attribute. Attributes inside a symbol do not have to be attached to anything. In order to see hidden attributes in gschem select **Edit**->**Show/Hide Inv Text**.
-  * There is a symbol content versioning system in libgeda which is based on the ''symversion='' attribute. Please see the [[master_attributes_list|Master Attribute Document]] for more information on using this versioning scheme.
+  * There is a symbol content versioning system in libgeda which is based on the ''symversion='' attribute. Please see the [[master_attributes_list#symversion|Master Attribute Document]] for more information on using this versioning scheme.
 ==== Graphics ====
   * Lines, boxes, arcs, and any other graphics should be color number 3 (graphic | green).
-  * Polarity bubbles should be color number 6 (logic bubble | cyan)
+  * Polarity bubbles should be color number 6 (logic bubble | cyan).
   * If you are unsure on how to make a new symbol look or how big to make a new symbol, look at the existing symbols to get a feel for the appropriate appearance and size.
@@ Line 148: / Line 153: @@
   * Pins should all be 300 mils (3 grid spaces) long.
   * For pins which are next to a logic bubble, make the pins 200 mils (2 grid spaces) long and then make the logic bubble 100 mils in diameter. In order to draw a 100 mil diameter circle, you will need to change the snap spacing to 50.
-  * A pin has two ends: one end has a red endpoint and one end that does not. The red endpoint is where nets can be connected. You can either rotate the pin so that this active end is in the right place or manually edit the symbol file changing the "whichend" parameter on the pin object. See the File Format document for more info.
+  * A pin has two ends: one end has a red endpoint and one end that does not. The red endpoint is where nets can be connected. You can either rotate the pin so that this active end is in the right place or manually edit the symbol file changing the "whichend" parameter on the pin object. See the [[file_format_spec#pin|File Format document]] for more info.
   * Be that all endpoints of pins which are meant to be connected to are on the 100 mil grid. The endpoint which is not active can be off the grid if necessary.
   * Pins should be color number 1 (pins | white).
@@ Line 160: / Line 165: @@
 ==== Electrical ====
-  * Do not draw power and ground pins. That information will be conveyed using attributes (see the netattrib document).
+  * Do not draw power and ground pins. That information will be conveyed using attributes (see the [[na_howto|net= attribute mini-HOWTO]]).
   * The above rule can be broken if necessary, but keep in mind most of the standard library does not have power pins showing.
   * Keep in mind, symbols are supposed to be symbolic, they do not represent the physical package that the device comes in.
@@ Line 180: / Line 185: @@
 This section provides a simple example which tries to follow all of the above rules. This symbol is of a 7400 (NAND gate).
-<code>v 20031231 1
+<code gschem 7400-1.sym>v 20031231 1
 L 300 200 300 800 3 0 0 0 -1 -1
 T 300 0 9 8 1 0 0 0 1
@@ Line 246: / Line 251: @@
 net=GND:7
 T 500 2650 5 10 0 0 0 0 1
-documentation=%%http://www-s.ti.com/sc/ds/sn74hc00.pdf%%
+documentation=http://www-s.ti.com/sc/ds/sn74hc00.pdf
 </code>
@@ Line 256: / Line 261: @@
 {{:geda:symbol_7400-1.png|:geda:symbol_7400-1.png}}

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