The first word in the file is a check code, that can be used to see that the file is actually a Sil format file. This word has two possible values, octal 34562 and 34563. The second value has been adopted as part of the design automation process to indicate that a Sil schematic file has been "build" into a wire-list file via the Build process.

Following this word are a secession of "item blocks" that describe the contents of the Sil drawing. An Item block has the following form:

All coordinate value are expressed in "Alto Screen" units and are referneced to the upper left hand corner of the screen.

Notice that descriptions of library fonts 5 through 9 characters are not defined within this Sil file. A table is filled in by Sil during input, and later the library files indicated in the user profile are opened, and the front of the file is scanned for items defining the required character codes for each of the library fonts characters.

TrueFonts: TYPE ~ [0..3];

MainFile: TYPE ~ [4..4];

LibraryFile: TYPE ~ [5..9]; declared in the definitions

SilFile: TYPE ~ [4..9];

InternalFonts: TYPE ~ [0..15];

InternalMacroFonts: TYPE ~ [8..13];

InternalFileMacroFonts: TYPE ~ [8..8];

InternalTrueFonts: TYPE ~ [0..7];

InternalLibraryFile: TYPE ~ [9..13];

InternalRopeFonts: TYPE ~ [0..13];  -- those fonts which do not denote boxes. See below

InternalBoxFonts: TYPE ~ [14..15];

InternalForegroundBoxFonts: TYPE ~ [14..14];

InternalBackgroundBoxFonts: TYPE ~ [15..15];

mainFile: MainFile ~ 4;

internalFileMacroFont: InternalFonts ~ 8;

foregroundBoxFont: InternalFonts ~ 14;

backgroundBoxFont: InternalFonts ~ 15;

Color: TYPE ~ [0..15];

colorTable: ARRAY Color OF CD.Layer ~ [CDSil.xneutral, CDSil.xred, CDSil.xyellow, CDSil.xgreen, CDSil.xcyan, CDSil.xviolet, CDSil.xmagenta, CDSil.xwhite, CDSil.xbrown, CDSil.xorange, CDSil.xlime, CDSil.xturquise, CDSil.xaqua, CDSil.xultraviolet, CDSil.xpink, CDSil.xsmoke];

neutralColor: Color ~ 0;

Font: TYPE ~ RECORD [

cellFonts: ARRAY InternalTrueFonts OF ARRAY BOOL OF Font;

ObjectName: TYPE ~ CHAR[' .. '~]; -- Only printing characters are used

MacroName: TYPE ~ CHAR['! .. '~]; -- All but <space>

mainObject: ObjectName ~ ' ; -- object whose name is <space>

SilObject: TYPE ~ RECORD [

SilObjectList: TYPE ~ LIST OF SilObject;

Macro: TYPE ~ RECORD [

MacroPtr: TYPE ~ REF Macro ← NIL;

MacroFile: TYPE ~ ARRAY ObjectName OF MacroPtr;

allMacros: REF MacroFile ← NIL;

coloredMacros: ARRAY Color OF CD.Object; -- the other stuff is in the neutral macro record

silDesigns: ARRAY SilFile OF LibraryDesign; -- need all because of imports

silProfilePrefix: Rope.ROPE ~ "Sil.Font";

cdSilProfilePrefix: Rope.ROPE ~ "Chipndale.chipnsil.Library";

lambda: INTEGER = CDSil.cdsil.lambda; -- Sil uses integers throughout

lambdaAltoScreenHeights: INTEGER ~ lambda * 808;

Gets from the user profile the fonts and makes the names for the Chipndale fonts. For the moment we consider only the display font, as Cedar Sil does. The Chipndale fonts are made only when they are referenced the first time.

}; -- end SetFonts

fullName: Rope.ROPE;

fullName ← Rope.Cat ["Xerox/TiogaFonts/", cellFonts[nr][italic].name];

In the version of Cedar Sil as of today, November 26, 1986 4:06:59 pm PST, there is a new command (^A) that allows you to use either strike or spline fonts for editing. However, it is not recorded in the Sil file which one you used to create the document. The Sil specification says that fonts are strike fonts, and that is what you get. If the document is scrambled when you read it because it was created with spline fonts, you lose: LIFE IS HARD! However, if you print the ChipNSil file using Nectarine, everithing will look OK.

cellFonts[nr][italic].descr ← CDTexts.MakeFont [name: fullName, scale: lambda];

IF cellFonts[nr][italic].descr = NIL THEN {

}; -- end MakeCDFont

Transforms all Sil macros to Chipndale cells. If a macro contains a macro from another macro file, the following policy is adopted: We try to import it an abort if we fail to do so.

FOR obj: MacroName IN MacroName DO

ENDLOOP;

IF ((allMacros[mainObject] # NIL) AND (allMacros[mainObject].cdCellPtr = NIL)) THEN

IF debugAll THEN TerminalIO.PutRope ["Sil macro file converted to Chipndale model.\n"]

}; -- end ConvertSilFile

Reads a single macro file.

sBlock: SilBlockRef ← NEW [SilBlock];

largesBlock: LargeSilBlockRef ← NEW [LargeSilBlock];

largeFormat: BOOL ← FALSE;

block: LONG POINTER ← NIL; -- either sBlock or largesBlock

bytesInSilItemBlock: INTEGER; -- depends on above

ENABLE BEGIN

list: LIST OF Rope.ROPE;

length: NAT;

name: Rope.ROPE;

IF length = 1 THEN name ← list.first

ELSE BEGIN

IF convLibEachTime THEN TerminalIO.PutRope ["\nAll libraries will be converted as they are referenced.\n"]

ELSE TerminalIO.PutRope ["\nIf they exist, the libraries specified in the user profile entries 'ChipNDale.ChipNSil.Library%' will be used. Delete them to force the creation of new ones.\n"];

Fluch cache to avoid colored cells to be inherited by next design:

FOR color: Color IN Color DO coloredMacros[color] ← NIL ENDLOOP;

synopsis ← ReadSilLibrary [5];

[] ← CDViewer.CreateViewer [design: synopsis]; CDOps.Redraw [synopsis] -- optional

EXITS

END;