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mboudreaux
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2/06/2008 10:30 AM
When I run simple commands in the command prompt like: "set X [get_nets -of_objects $port]" I get the net I am looking for, as well as some random variable - ie: "U_global_control_rtl/sbr_efadd_oΎ] 0x5500" What is the 0x5500?? That ends up being the value stored in the variable "X". Any help would be awesome!

mboudreaux
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2/06/2008 11:45 AM
Forgot to mention... I am running 64bit on Linux.

BobD
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2/06/2008 12:12 PM
"get_nets" is a CTE-TCL command. CTE-TCL commands return special pointers that other CTE-TCL commands can operate on, or collections of special pointers. For example, you could do something like this: set port [get_ports BG_scan_in_2] set X [get_nets -of_objects $port] report_property $X (pardon the formatting, the following table is aligned in the console but appears unaligned here in the forum): property \| value ------------------------------------------------- capacitance_max \| 0.002 capacitance_min \| 0.002 driver_pins \| hierarchical_name \| BG_scan_in_2 has_detailed_parasitics \| false is_dont_touch \| false is_hierarchical \| false load_pins \| name \| BG_scan_in_2 object_type \| net pin_capacitance_max \| 0.002 pin_capacitance_min \| 0.002 wire_capacitance_max \| 0.000 wire_capacitance_min \| 0.000 If you had a collection, you could iterate through each pointer in the collection with "foreach_in_collection". You can find more information on these types of commands in the FE Text Command Reference (fetxtcmdref.pdf) shipped with the software under the "Advanced Timing Tcl Scripting Commands". Feel free to post back if this wasn't the kind of information you were looking for, or if you have further questions in this area. Hope this helps, Bob

mboudreaux
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2/06/2008 2:33 PM
In your example, the value of "X" would be something like "0x5cff" instead of the name of the net attached to BG_scan_in_2. If I were to enter your code in my FE, it would error as it would not find the properties of "0x5cff". Any ideas?

BobD
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2/06/2008 4:05 PM
Here is my log file cut and pasted as is: [DEV]encounter 4> set port [get_ports BG_scan_in_2] 0x2 [DEV]encounter 5> set X [get_nets -of_objects $port] 0x3 [DEV]encounter 6> puts $X 0x3 [DEV]encounter 7> report_property $X property \| value ------------------------------------------------- capacitance_max \| 0.002 capacitance_min \| 0.002 driver_pins \| hierarchical_name \| BG_scan_in_2 has_detailed_parasitics \| false is_dont_touch \| false is_hierarchical \| false load_pins \| name \| BG_scan_in_2 object_type \| net pin_capacitance_max \| 0.002 pin_capacitance_min \| 0.002 wire_capacitance_max \| 0.000 wire_capacitance_min \| 0.000 [DEV]encounter 8> report_property 0x3 property \| value ------------------------------------------------- capacitance_max \| 0.002 capacitance_min \| 0.002 driver_pins \| hierarchical_name \| BG_scan_in_2 has_detailed_parasitics \| false is_dont_touch \| false is_hierarchical \| false load_pins \| name \| BG_scan_in_2 object_type \| net pin_capacitance_max \| 0.002 pin_capacitance_min \| 0.002 wire_capacitance_max \| 0.000 wire_capacitance_min \| 0.000 As you can see, whether I pass "$X" or "0x3"- report_property still works as I'd hope it would. Please give it a try. If it still doesn't work for you there may be some other problem conspiring against you. If that's the case, please do post back or open a service request at http://sourcelink.cadence.com. Thanks, Bob

mboudreaux
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2/07/2008 4:53 AM
Your example works for me and gets the same output you get... How do I get a variable to "equal" only the associated net name to which BG_scan_in_2 is attached?

BobD
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2/07/2008 5:24 AM
I'm glad to hear that worked for you. Now that you see the list of property/value pairs output by report_property, you can set any one of the properties values to a variable using "get_property": [DEV]encounter 11> set net_name [get_property $X name] BG_scan_in_2 [DEV]encounter 12> puts $net_name BG_scan_in_2 It might be worth mentioning that there are several db access mechanisms that are available in Encounter. The mechanism you're using right now I call CTE-TCL. They're the way to go when you're interested in probing the design from a timing perspective. A new mechanism that debuted in our 7.1 release is called "dbGet". It provides a more SKILL-like way to probe the db. I say SKILL-like not from a syntax perspective, but in terms of the way it presents information to the user in a relational/linked manner. Here's an example of how you would do the same thing you did with CTE-TCL with dbGet: [DEV]encounter 20> dbGet top.terms.name clk reset rcc_clk {addressΑ]} {addressΐ]} {addressΏ]} {addressΎ]} {din⎛]} {din⎚]} {din⎙]} {din⎘]} {din⎗]} {din⎖]} {dinΗ]} {dinΖ]} {dinΕ]} {dinΔ]} {dinΓ]} {dinΒ]} {dinΑ]} {dinΐ]} {dinΏ]} {dinΎ]} digit_clk {doutΕ]} {doutΔ]} {doutΓ]} {doutΒ]} {doutΑ]} {doutΐ]} {doutΏ]} {doutΎ]} dout_flag test_mode scan_en BG_scan_in BG_scan_out BG_scan_in_2 BG_scan_out_2 [DEV]encounter 21> dbGet top.terms.name BG_scan_in_2 BG_scan_in_2 [DEV]encounter 22> dbGet -p top.terms.name BG_scan_in_2 0x15100248 [DEV]encounter 23> set term [dbGet -p top.terms.name BG_scan_in_2] 0x15100248 [DEV]encounter 24> dbGet $term.? term: cell inOutDir isInput isOutput isScanClk isSpecial isTieHi isTieLo name net objType orient pStatus type [DEV]encounter 25> dbGet $term.net.name BG_scan_in_2 I don't mean to confuse you with another db access mechanism- but depending on what information you're trying to get (and the eda tools you've used in the past) you might find one mechanism easier than the other. One note: hex pointers from dbGet are not interchangable with CTE-TCL hex pointers. To pass information back and forth between dbGet and CTE-TCL you need to re-get the pointer by name. Here's an example: From CTE-TCL to dbGet: [DEV]encounter 7> set port [get_ports BG_scan_in_2] 0x6 [DEV]encounter 8> set port_name [get_property $port hierarchical_name] BG_scan_in_2 [DEV]encounter 9> dbGet top.terms.name $port_name BG_scan_in_2 [DEV]encounter 10> set term [dbGet -p top.terms.name $port_name] 0x14a91a98 [DEV]encounter 11> dbGet $term.net.name BG_scan_in_2 dbGet's usage is: Usage: dbGet [-d] [-p#] [-u] [-regexp] .[obj_type][{.attr_name\|.?\|.??\|.?h} [pattern]] More information on dbGet is available in the soceDBAref.pdf document shipped with the software. Thanks, Bob

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