Answers Database
 
 
 FPGA Configuration: Address Pins A18 - A21 are optional for XC4000EX only 
 
 Record #1984
Product Family:  Software 
 
Product Line:  FPGA Implementation 
 
Product Part:  bitgen 
 
Product Version:  1.1.1a 
 
Problem Title: 
FPGA Configuration: Address Pins A18 - A21 are optional for XC4000EX only  
 
 
Problem Description: 
Urgency: Standard 
 
General Description: 
The Configuration Address Pins A18, A19, A20, A21 are all high at the beginning of a Master Parallel 
  configuration. 
 
 
Solution 1: 
 
Since these lines are optional, they will act like unconfigured IOs until the portion of the bitstre
am to activate them is received.  This means that A18-A21 will float high at the beginning of config
uration.  For Master Parallel Up configuration they need to be low from the beginning.	This can be
accomplished with a pulldown. 
 
The Address Pins A18-21 are only activated by a bitgen option -g addresslines:<value>. The value spe 
cifies the total number of address lines to be activated.  By default this number is 18.  If you wan
ted A18 - A21 to be activated the bitgen syntax would be: 
 
bitgen -g addresslines:22 
 
 
 
Solution 2: 
 
In order to set the option to activate the upper address lines 
from the Design Manager GUI, you will need to perform the 
following steps : 
 
1.  Create a project for your design. 
 
2.  From the Utilities pull-down menu select Template Manager. 
 
3.  Select the "xc4000" Family from the top pull down menu and 
        then select the "Configuration Template" buttton from the 
        Template Manager window. 
 
4.  Select the New button and specify a name for your personal 
        configuration template. 
 
5.  Being sure your template name is selected in the "Template 
        List" window and press the "Customize" button. 
 
6.  Once the Customize window appears, type into the following 
        fields (WEBIMAGE 1:Template Manager Customize Window) : 
 
        Program Name : bitgen 
        Program Options : -g addresslines:22 
 
7.  Press the "Set" button and then select "OK". 
 
8.  Press the "Edit" button and select all other configuration 
        options you wish to use for your design. 
 
9.  Close the Tamplate Manager 
 
10. Implement your design selecteing from the Implement Options 
        window the configuration template you have just created. 
 
 
For more information on the Template Manager consult the 
"Design Manager/Flow Engine Refernce/User Guide" from your 
Dynatext On-line Document Browser. 
 
 
 
 End of Record #1984 - Last Modified: 07/13/98 16:07  |