MOTOROLA Timing Diagram Quick Reference Part 1 Diagram Conventions In representing the timings for the DSP56307, certain conventions were chosen to make information retrieval as easy as possible. They are as follows: a. Designating assertion level In designating the assertion level for DSP56307 pins, we choose to represent a low-asserted signal with the symbol # inserted immediately following the signal mnemonic. b. Parameter Window format The Parameter window lists all the timings in a tabular format. Above these timings, some information about the revision and part are given. Table 1: Parameter Window for Fig2_4.td Name Formula Part_Number [,] Data_Reference [,] Revision_Information [,] Mode_Description [,] Aliases [,] $DSP motorola:dsp56307:modes:$freq $freq 100 Constants [,] freq 100 TC ((1/freq)*1000) duty.cycle 50 rising.jitter 0 falling.jitter 0 Input_Constraints [,] t11 $DSP:t11(TC) Output_Delays [,] t12 $DSP:t12(TC) Min Max Margin 100 10 50 0 0 100 10 50 0 0 5.9 10 <1.1,3> 33.5 207.5 As seen in the table above, the Part Number is shown in the first line, followed by the Data Reference information. The Data Reference information details the document the timings were taken from. The Revision Information tells the user which version of the diagrams they are looking at. The Mode Description gives the name of the specific timing being considered. The figures shown in the description portion of the table relate to the figure numbers shown in the data reference manual used. The next section of table declarations are the Aliases. Examples of aliases are $freq and $DSP. $DSP references which DSP libraries are being used and $freq defines which choice of libraries should be referenced. Below Aliases are the Constant values. The Constant values define certain parameters required to calculate the timings requested lower in the table. The user may change © Motorola, Inc., 1998 Timing Diagram Quick Reference Row 1 V 2 V 3 V 4 V 5 V 6 P 7 A 8 V 9 V 10 V 11 V 12 V 13 V 14 V 15 C 16 V 17 D these values as appropriate for their given application. One constant is freq. This constant is used to calculate the period of the clock, TC. This value is used throughout the calculations for timing parameters. In this example, freq is set to 100 MHz. The last two general sections are the Input Constraints and Output Delays. These are the timings specified in the timing diagram window. Here the user can see the min/max values as well as the margins. All of the diagramÕs Parameter windows are organized in this manner. Part 2 How-ToÕs TimingDesigner has an extensive help function, so all of the following items are discussed more completely within that function. However, a few guides are given here to get the user started. a. Add libraries to TimingDesigner path In order to use the Motorola signals libraries, the library must be added to the TimingDesigner path. To do this, go to the File menu within either the Parameter or Diagram window. Select ÒAccess Synchrony Data.Ó Now you will need to browse through your directory structure to get to the motorola directory wherever you installed the libraries and diagrams. In this directory is a tdproj.res file. Select this file and hit the OK button. The Motorola libraries are now accessible. b. Change Clock Attributes When viewing and working with a diagram, you may wish to change the clock speed or other clock attributes. There are two ways to do this. If changing clock frequency, rise time, or fall time, you may go to the rows in the Parameter window with theses designated names (under the Constants heading) and change the value. All changes are reflected in the Diagram window. If you want to change any other attributes, go to the Diagram window and double click on the Ò1Ó button to the left of the clock signal. This brings up a clock attribute box that you can change as desired. c. Change Wait states Many timing calculations rely on a wait state constant declaration. This should be modified as it fits for the system being designed. This value is given in the Parameter window under the Constants heading and can be changed as needed for an application. The wait state value under the Aliases section must also be changed. The aliases define which library to go to, and this is required to choose the correct timing expression for the chosen wait state. d. Move End Marker If you need to adjust the clock frequency, or are connecting the DSP56307 to another device, the end marker may be in an inconvenient position. To move this marker, select the marker in the ruler section. Click on the Source button and then click on the clock edge where you want the end marker to be sourced. The marker will change accordingly. e. Move Signal edges Signal edges can be moved to a specific location, or moved in a more general manner. To move a signal edge to a specific time, double-click on the edge and enter the earliest/latest time as desired. If a more general move is all that is needed, you can simply drag the edge to where youÕd like it to be. Sometimes an edge may be locked. To turn off this lock, double-click on the edge and deselect the Lock option. Motorola Timing Diagram Quick Reference 2-2 (7/1/98) f. View Threshold Marks When opening the diagrams, the threshold marks on the figures may not be visible. If you would like to see the threshold marks, go to the View menu and select Display Preferences at the bottom of the menu. A dialog box will come up and you can select/deselect the threshold marks as you wish. Threshold timings are not provided for all figures, but the software will show the marks anyway. If a timing is in question, check the 56307 Data Sheet for verification. g. Hide Timings/Gray Timings There may be a timing that you are not interested in seeing. If you would like to simplify your diagrams, you can hide or gray the timing so that you donÕt have to delete it from the diagram. To do this, select the timing and go to the View menu. Near the bottom of the menu you can select or deselect the ÒHideÓ option. If you would like the timing to be less dark, but still visible you can also select the ÒHidden in GrayÓ option. h. View Timing Margins Instead of Timing Name There may be times when you are more concerned with the timing margin than the timing name. If this is the case, double-click on the timing parameter (highlighted in either red or green). A dialog box will appear. In the lower left corner of the box (the Appearance section) you may select which values about the timing to present. One option is Margin, but other options are also available. Choose which option you prefer and it will be reflected in the diagram window.. We hope that this quick list of How-ToÕs is helpful to get you started. Refer to the on-line help for answering any other questions that may come up. Motorola Timing Diagram Quick Reference 2-3 (7/1/98)