Merge pull request #7 from ElectricPotato/zigzag-scan-chain
change scan chain instantiation order
diff --git a/configure.py b/configure.py
index 8dcc6f2..5892284 100755
--- a/configure.py
+++ b/configure.py
@@ -238,14 +238,23 @@
with open("openlane/user_project_wrapper/macro.cfg", 'w') as fh:
fh.write("scan_controller 80 80 N\n")
for row in range(rows):
- for col in range(cols):
+ if(row%2 == 0):
+ col_order = range(cols)
+ orientation = 'N'
+ else:
+ #reverse odd rows to place instances in a zig zag pattern, shortening the scan chain wires
+ col_order = range(cols-1, -1, -1)
+ orientation = 'S'
+ for col in col_order:
# skip the space where the scan controller goes on the first row
if row == 0 and col <= 1:
continue
if num_macros_placed < self.num_projects:
macro_instance = self.projects.get_macro_instance(num_macros_placed)
- instance = "{} {:<4} {:<4} N\n".format(macro_instance, start_x + col * step_x, start_y + row * step_y)
+ instance = "{} {:<4} {:<4} {}\n".format(
+ macro_instance, start_x + col * step_x, start_y + row * step_y, orientation
+ )
fh.write(instance)
num_macros_placed += 1
