


        ==READ.ME========Tango-PCB Series II========Update Version 1.07==


        
        This READ.ME file supplements the Tango-PCB Series II Reference
        Manual and Version 1.02 Release Notes.  Please note that all the
        files listed in the printed Version 1.02 Release Notes are
        included with Version 1.07, but not necessarily on the same disk.
        
        The new features and problems fixed in Tango-PCB Version 1.07 are
        described below.


        NEW EDITING FEATURES

        1.  Version 1.07 has been streamlined to support slightly larger
            PCB files.
        
        2.  The cursor now appears for all editing commands.  In the
            previous version, for example, the cursor was visible during
            the Place String command but disappeared during the Place Pad
            command.
        
        3.  Version 1.07 fixes all problems reported when running Tango-
            PCB under versions of DOS earlier than 3.0.
        
        4.  The new EVXEGA.DRV graphics driver supports the Everex EV-654
            graphics card.  This card does not properly display the 8 x 8
            character font in graphics mode.  The new driver works around
            this limitation.
        
        5.  We have had reports of display problems when using the Kaypro
            EGA card with a BIOS of version 81-1142A.  This problem is
            not limited to Tango-PCB.  To fix the problem, contact Kaypro
            to request the newest BIOS version 81-1142D.
        
        6.  We have had reports of problems when using the Logitech C7
            mouse and its MOUSE.COM driver file.  This driver file
            resides in an area of upper memory used by Tango-PCB.  The
            memory conflict between Tango-PCB and the mouse driver can
            cause unexpected results.  To avoid this problem completely,
            we recommend that you install the Logitech C7 mouse using the
            MOUSE.SYS driver file.  Follow the installation instructions
            in the Logitech manual.
        
        7.  When flipping a component that contains surface pads from the
            Top to the Bottom layer, all surface pads in the component
            are now moved to the Bottom layer, as documented in Sections
            11.3 and 11.6 of the manual.
        
        8.  Version 1.07 ensures the proper orientation when flipping and
            rotating components.  In the previous version, if you flipped
            a component and then rotated it either 90 or 270 degrees, the
            rotation would not be performed correctly.
        





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        9.  You can now use the Edit Pad command to correctly edit all
            matching pads, as documented in Section 8.2.3 of the manual.
            This operation did not work properly in the previous version
            under the following conditions: Two components with
            rectangular DIP pads are placed on the board and one is
            rotated 90 degrees.  If you edit pad one of the first
            component and direct the program to edit all matching pads,
            Tango-PCB would change the orientation of pad one of the
            second component so that it was no longer rotated.
        
        10. You can now use the Place String command to correctly place
            very large numeric strings.  In the previous version, the
            program rounded off any numeric string larger than 32,767.
        
        11. All text strings in a PCB file are now processed correctly
            when you load the file.  In the previous version, Tango-PCB
            displayed an error message for each text string in the PCB
            file that contained a double-quote mark (") followed by a
            slash (/).
        
        12. Version 1.07 fixes the intermittent problems caused by
            clicking the mouse.  In the previous version, clicking the
            mouse a number of times would occasionally cause display
            problems with text strings.  In some cases, this problem
            could also freeze the system.  To continue, it was necessary
            to re-boot the computer.
        
        13. There are no longer any unnecessary display redraws when
            running the Jump Net command or when accessing on-line help.
        
        14. The screen is now always redrawn correctly after displaying a
            menu, dialog box, or error message.
        
        15. Version 1.07 displays an error message when you attempt to
            load any file that is not a valid Series II PCB file.
        
        16. If you have made changes to the current design during the
            editing session, the program now always prompts you to save
            the changes and exit, exit without saving the changes, or
            cancel the File Quit command.  In the previous version, the
            program did not display this prompt if you had interrupted
            the last File Save operation by pressing <RightMouse> or
            <Esc>.
        
        17. The File Save command's Save Backup option now always renames
            the current file with the extension .BAK before saving the
            new file, as documented in Section 6.3.4 of the manual.  In
            the previous version, Tango-PCB created a .BAK file when you
            first saved a file.  For all subsequent save operations,
            however, the program saved the new file without updating the
            backup file.  Note that all file save operations involve the
            creation of a scratch file in the subdirectory of the disk
            where the file is to be saved.  This means that the
            destination subdirectory must have enough space to contain



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            the scratch file (which is the size of the current design),
            the resulting saved file, as well as the backup file with the
            .BAK extension, if that feature is enabled.  If the ultimate
            destination is to be a floppy disk, we suggest that the
            design be first saved on the hard disk where there is likely
            to be sufficient space, then copied via DOS to the floppy.
        
        18. When listing files (for example, when using the File Load and
            File Save commands), you can now use wildcard characters in
            the pathname, as documented in Section 5.3.1.4 of the manual.
            The previous version would not accept wildcards when listing
            files in a directory other than the current directory.
        
        19. For the Nets Load command, any errors detected when loading
            the net list will no longer consume extra memory.  In the
            previous version, the program consumed a large chunk of
            memory for each net list error it displayed.  This problem
            sometimes resulted in an out-of-memory error, in which case
            the net list was not properly loaded.
        
        20. When loading a PCB file that contains net list information as
            a block, the net list information for the two files are
            merged.  The previous version displayed error messages
            concerning duplicate nets and insufficient memory.
        
        21. When loading a net list, Tango-PCB now correctly connects all
            surface pads that belong to the Power or Ground planes.  The
            program displays a connection from the surface pad to a
            through-hole pad belonging to the same plane.
        
        22. The Nets Verify command considers only the drill hole
            dimensions for mounting holes on the inner board layers.
            This lets you place items within the mounting hole pad
            dimensions on the inner layers (but not within the drill hole
            dimensions).  On the Top and Bottom layers, however, Tango-
            PCB considers the outside dimensions of the mounting hole.
            In this way, the program allows for material such as screw
            heads and nuts which extend past the hole diameter on the Top
            and Bottom layers but which would have no effect on the inner
            layers.
        
        23. Version 1.07 no longer allows you to place any part of an
            item outside the boundaries of the workspace.  The X and Y
            coordinates for the item must be greater than or equal to 0
            and less than or equal to 32000.  If you attempt to place any
            part of an item outside the workspace, the computer beeps.
            You can then continue to move the item until it is positioned
            at a valid location.
        
            If you load a PCB file created with a previous version,
            Version 1.07 will not load any part of the file that is
            outside the workspace boundaries.  Note that this includes
            tracks at small X or Y coordinates which have a width causing




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            them to extend beyond the boundary.  In this case, Tango-PCB
            will display an error message to inform you of the problem.
        
            If it is necessary to load the parts of the file which are
            ignored because of the error, use the File Load Block
            commands which will place the entire PCB with its origin at
            the cursor.  Then, use the Move Block commands to move it to
            a more desirable position.
        
        24. You can now move a component to any location within the
            boundaries of the workspace.  In the previous version, if you
            moved a component to a location in which the Y coordinate was
            greater than or equal to 30600, running another command (such
            as Move String or Place Component) would freeze the system.
            To continue, it was necessary to re-boot the computer.
        
        25. With Version 1.07 it is now possible to effect a quick save
            of the current PCB design by clicking the mouse over the
            filename area on the bottom status line.  This action writes
            the current PCB design to the subdirectory containing the
            PCB.EXE program file and gives it the same design filename,
            followed by the .TMP extension.  Any previous quick save of
            the design is overwritten by this action.  It is good design
            practice to save these 'snapshots' of the design at regular
            intervals.  Should there be a need to recover a design after
            a system crash or other error, simply use DOS commands to
            rename the file, changing the .TMP extension to the .PCB
            extension used for standard PCB files.
        
            When clicking on the file name to save a .TMP file, if the
            file is still untitled, the File Save dialog box will appear.
            Enter the file name as normal.  The .PCB extention will be
            added to the file name as documented and the temporary file
            will be given the .TMP extention.
        
        26. The bug, which under certain circumstances caused a program
            hang when using UNDO during the placement of tracks, has been
            identified and fixed.
        
        
        NEW OUTPUT FEATURES
        
        1.  A Driver entry box has been added to the second Output
            Plot/Print dialog box.  The Driver entry box, located just
            above the Drivers list box, lets you type the name of the
            plotter or printer driver.  You can also select the driver
            from the list box.
        
            The ability to enter the driver directly rather than
            selecting from a list is critical when working with very
            large PCB files.  If the current PCB file requires too much
            memory, the program displays the message "Insufficient memory
            to display list box" when you attempt to display the second
            Output Plot/Print dialog box.  In this case, press any key to



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            continue.  Tango-PCB displays the second dialog box without
            listing the available drivers.  You can type the desired
            driver in the Driver entry box or use the current driver.
        
            Note that when typing a driver name in the Driver entry box,
            you must enter the name of the driver as it's displayed in
            the Drivers list box (when memory is sufficient to display
            the list box).  You can, however, enter either upper-case or
            lower-case characters and any number of spaces.
            
        2.  The Rotate option has been added to the first Output
            Plot/Print dialog box.  When you enable this option, Tango-
            PCB rotates the board 90 degrees counterclockwise when
            plotting or printing.  The Rotate option is especially useful
            when printing a wide design on an 8.5 x 11-inch sheet of
            paper.  If desired, you can enable both the Mirror Image and
            Rotate options for plotting or printing.  In this case, the
            program first mirrors the board and then rotates it.
        
        3.  The default filename for plotting and printing to a file has
            been changed in the second Output Plot/Print dialog box
            (Section 16.2.10 of the manual).  For plotters, the default
            filename is <name>.PLT in the current directory, where <name>
            is the base name of the currently loaded PCB file.  For
            printers, the default filename is <name>.PRN in the current
            directory.  For example, if you're plotting the design
            DEMO1.PCB to a file, Tango-PCB will display the default
            filename DEMO1.PLT.  If you're printing the same file, the
            default filename is DEMO1.PRN.
        
            If you enter a different filename in the Output File entry
            box, Tango-PCB will remember this name and use it as the
            default filename for the duration of the editing session.
            Note that when you exit the program, this filename is not
            saved in the PCB.INI file.  If you quit Tango-PCB and then
            start a new editing session, the program again uses the
            default filenames <name>.PLT and <name>.PRN for
            plotting/printing to a file.
        
        4.  The plotter drivers have been modified to speed up plotting.
        
        5.  When plotting/printing the Power or Ground plane using a
            single color, Version 1.07 plots all thermal and direct
            connections to the plane, as well as clearances.  Since the
            Power/Ground planes are plotted in the negative, all
            clearances (holes that are not connected to the plane) are
            drawn, direct connections are not drawn, and thermal
            connections are drawn as four narrow arcs of clearance.
        
            For multi-color plotting/printing, Version 1.07 draws a small
            cross (+) in the center of a pad to indicate a thermal
            connection.  A direct connection is indicated by an X in the
            center of a pad.  The cross and X symbols are drawn the same
            size as the pad dimensions (not the hole diameter).



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        6.  When plotting/printing with the Mirror Image option enabled,
            all items on the board are now mirrored correctly.  In the
            previous version, some items were mirrored and some items
            (including text strings, mounting holes, and targets) were
            not.
        
        7.  When using the HPGL plotter driver, Tango-PCB no longer sends
            the commands AA, CT, and GM.  This allows the driver to
            maintain compatibility with older HPGL plotters that do not
            understand these commands.  These older plotters include the
            HP 7090A, 7440A, 7470A, 7475A, 9872A, and 17440A.
        
        8.  Some users have had difficulty configuring their Calcomp
            plotters correctly for Tango-PCB.  There are specific
            settings required on all plotters in order to communicate
            with different software packages.  The recommended settings
            for the Calcomp plotter so that it will work correctly with
            Tango-PCB are as follows:
        
              Format:         PCI mode
              Baud Rate:      9600
              Byte Length:    8 bits
              Stop Bits:      1 bit
              Parity:         None
              Handshake:      Direct Control (Hardwire or XON/XOFF)
              Sync Char:      002
              Number Sync:    1
              End Message:    03
              Checksum:       Disabled
        
            After setting the plotter, use Tango-PCB's Setup
            Communications command to configure the serial port to match
            the plotter settings.
        
        9.  When setting the offset on Calcomp plotters, you can now move
            the plotter pen interactively by clicking on the LEFT, RIGHT,
            UP, and DOWN pushbuttons, as documented in Section 16.2.13 of
            the manual.
        
        10. After you set the offsets for a plotter and click on OK to
            plot, Tango-PCB no longer displays the error message "Port
            not setup".
        
        11. When plotting, the X and Y correction values now remain the
            same as entered.  In the previous version, the correction
            values sometimes drifted by a thousandth or two.
        
        12. An automatic offset feature has been added to the printer
            drivers.  When printing, the upper-left corner of the design
            will always be positioned in the upper-left corner of the
            paper.  If you enable the Rotate option, the upper-left
            corner of the design AFTER rotation will be positioned in the
            upper-left corner of the paper.



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        13. For designs that do not fit on a single sheet of paper, all
            printer drivers now produce a slight overlap between sheets.
            This makes it easier to glue or tape the sheets together to
            form the complete board.
        
        14. New printer drivers have been added which support the A4 and
            Legal page sizes on the HP LaserJet.  These are:  HPLASER
            A150 and HPLASER A300 for the A4 (metric) size; and HPLASER
            L150 and HPLASER L300 for the Legal size.
        
        15. The paging for the HP LaserJet has been corrected.
        
        16. The paging has been corrected for all reports generated using
            the Output Reports command.
        
        17. The Statistics report, generated using the Output Reports
            command, now always lists the correct number of each item on
            the board.  In the previous version, the Statistics report
            showed an incorrect number of items if you had previously
            used the Move Component command.
        
        18. The Aperture Information report, generated using the Output
            Reports command, now details all errors related to the DRAW
            aperture.  In the previous version, the program did not
            report an error if the DRAW aperture was not assigned.
        
        19. Version 1.07 ensures that, under normal operation, you can
            generate CAM files using the Output CAM command without
            freezing the system.  In the previous version, if you deleted
            an item from the board and then ran the Output CAM command
            without first redrawing the screen, the program would freeze
            when generating CAM files.  Also in the previous version, the
            program would occasionally freeze after generating an N/C
            drill file.  In both cases, you had to re-boot the computer
            to continue.
        
        20. When generating CAM files using the Output CAM command, you
            can now interrupt the procedure by pressing <RightMouse> or
            <Esc>, as documented in Section 17.4.10 of the manual.  In
            the previous version, the program continued to generate the
            CAM files.
        
        21. All surface pads are now photoplotted correctly no matter the
            size of the aperture assigned to the pad.  In the previous
            version, there was a problem with filling in the surface pad
            correctly if you assigned the pad a draw aperture with a
            diameter just slightly smaller than the pad diameter.
        
        22. When you generate a photoplot file using Version 1.07's
            Output CAM command, you can use the photoplot file as input
            to two Tango-Tools utility programs.  After using GVIEWIZE
            (from the Tango-BBS) to convert Series II Gerber output to a
            format compatible with Version 3, you can view the file on



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            the screen using the GVIEW program and you can panelize the
            design using the PANEL program.  When generating the
            photoplot file, make sure you select the 5.3 format in the
            first Output CAM dialog box.  Also, since ACCEL no longer
            sells the Tango-Tools package, you must already have your own
            copies of the GVIEW and PANEL programs.


        A FEW IMPORTANT REMINDERS

        1.  We have had some confusion concerning the second Output CAM
            dialog box.  The CAM File Queue list box in this dialog box
            contains file definitions.  The file definitions are not the
            same as actual files on the disk.  When you click on the
            Delete pushbutton to delete a file definition from the CAM
            File Queue, the program does not delete any files on the
            disk.
        
            So if the file definitions are not real files, what are they?
            It might help to think of them as directions to the program
            for generating CAM files.  For example, if the CAM File Queue
            contains the definitions DEMO1.TOP, DEMO1.BOT, and DEMO1.SLK,
            clicking on the OK pushbutton directs Tango-PCB to generate
            the photoplot files DEMO1.TOP, DEMO1.BOT, and DEMO1.SLK.
        
            If you click on the Delete pushbutton to delete the file
            definition DEMO1.SLK, the program generates only the CAM
            files DEMO1.TOP and DEMO1.BOT.  It is important to note that
            if there is a file named DEMO1.SLK in the current directory,
            deleting the file definition DEMO1.SLK does not delete the
            DEMO1.SLK file.  To delete this file, you have to use the DOS
            DELETE command.
        
            What if there's a file named DEMO1.SLK in the current
            directory and you add the file definition DEMO1.SLK to the
            CAM File Queue?  In this case, clicking on OK directs Tango-
            PCB to generate a new photoplot file named DEMO1.SLK.  This
            new photoplot file overwrites the previous one.
        
        2.  When plotting final artwork, we strongly recommend that you
            do not enable the Mirror Image option for the Bottom layer.
            The mechanical inaccuracy inherent in all pen plotters causes
            items on the mirrored layer to be out of alignment with the
            items on all other layers.  This misalignment could lead to
            severe problems when fabricating and assembling the board.
        
            Why is misalignment only a problem when plotting a mirror
            image of the Bottom layer?  In Tango-PCB, each layer of a
            board is normally plotted as you would see it from the Top
            layer.  Due to the mechanical inaccuracy of the plotter,
            items may not be always be drawn exactly where specified in
            the PCB file.  However, since the plotter starts drawing from
            the same side of each layer, the inaccuracies tend to cancel
            each other out.  For example, if a pad is off by 10 mils on



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            the Top layer, it will also be off by the same amount and in
            the same direction on the Bottom layer.
        
            When you enable the Mirror Image option, the program plots
            the layer as it would be seen from the Bottom layer.  In
            effect, the layer is flipped.  In this case, compared with a
            layer that is plotted normally, the plotter starts drawing
            from the opposite side of the mirrored layer.  A pad that is
            off by 10 mils on the Top layer would be off by 10 mils IN
            THE OPPOSITE DIRECTION on the mirrored Bottom layer.  In this
            case, the Top and Bottom layer pads would be 20 mils apart!
        
            To avoid misalignment problems, plot all final artwork with
            the Mirror Image option disabled.  Also note that mirror
            imaging only causes problems when pen-plotting final artwork.
            Since photoplotters are much more accurate than pen plotters,
            you can use the Mirror Image option when generating a
            photoplot file without fear of misalignment.  You can also
            use the Mirror Image option when pen-plotting layers for
            check plots and documentation (such as the Bottom Assembly
            layer).
        
        3.  Due to memory constraints, the File DOS command will not, in
            most cases, allow you to execute DOS commands without
            quitting the Tango-PCB program.  The File DOS command will be
            of use only if you run it BEFORE loading and editing PCB
            files.  We've included a brief explanation for this problem
            below, which gives you some idea of the inner workings of
            DOS.
        
            In order to execute DOS commands, the operating system first
            must load its command interpreter (the file COMMAND.COM).
            This requires a set amount of contiguous memory ("contiguous
            memory" means a block of adjacent memory locations).  When
            you load and edit PCB files, however, the available memory
            tends to get fragmented.  By the time you run the File DOS
            command, it's unlikely that the required amount of contiguous
            memory remains.
        
            If you run the File DOS command and DOS cannot find the
            necessary memory to execute commands, type EXIT and press
            <Enter> to return to Tango-PCB (if DOS has not already
            returned to the program automatically).  When Tango-PCB is
            again in control, the program displays the error message:
            "Insufficient memory for COMMAND.COM".  You can then continue
            your editing session.
        
        4.  We have received a number of calls concerning the recommended
            procedures for defining and assigning apertures.  A brief
            tutorial on using the Output Apertures and Output CAM dialog
            boxes is included on the release disks in the CAMHINTS.TXT
            file.  Print and review this file if you have questions on
            defining or assigning apertures for creating photoplot files.
        



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