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#openlane
Title
# openlane
i

Ivan Rodriguez

06/04/2021, 7:19 AM
Hi, in the in the user proj example is defined the die area as
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set ::env(DIE_AREA) "0 0 900 600"
is this the maximum size for the user proj in caravel? or is only an example an can be increase?
h

Hieu Bui

06/04/2021, 8:01 AM
It is just an example. You can change it to fit your need.
i

Ivan Rodriguez

06/04/2021, 8:30 AM
so witch value is the maximum that still fits in caravel?
m

Matt Venn

06/04/2021, 8:48 AM
check the config for the user project area
that defines the max size
i

Ivan Rodriguez

06/04/2021, 8:50 AM
where is that file? is the user project wrapper ?
m

Matt Venn

06/04/2021, 8:53 AM
from memory, the user project wrapper includes some config from another directory called user project wrapper empty
and it's in there
h

Hieu Bui

06/04/2021, 8:54 AM
The maximum size is:
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set ::env(DIE_AREA) "0 0 2920 3520"
You can find it in 'caravel/openlane/user_project_wrapper_empty/fixed_wrapper_cfgs.tcl'
1
i

Ivan Rodriguez

06/04/2021, 8:55 AM
Thanks a lot for the help 😀
t

Tayyeb Mahmood

06/04/2021, 9:41 AM
set ::env(DIE_AREA) "0 0 900 600" #this is size of example macro.
set ::env(DIE_AREA) "0 0 2920 3520" #this is size of user_project_wrapper
I recommend that you use macro sizes at-least 100um less than wrapper dimensions.
👍 1
a

ALI AHMED

06/04/2021, 4:35 PM
@Rameen Anwar
r

Russell Friesenhahn

06/05/2021, 8:24 PM
regarding this, are you constraining your design size in any way? Based on @Tayyeb Mahmood comment would it be reasonable to
set ::env(DIE_AREA "0 0 2820 3420
or perhaps a little smaller for the actual user design that is within
user_project_wrapper
?
t

Tayyeb Mahmood

06/05/2021, 9:40 PM
Because user_project_wrapper has no std cells, a 50um HALO works best to connect IO, but macroplacer does not respect that, at least in my work. Therefore, it is best to place it manually by using macro.cfg.