Moved the simple_por ngspice simulations into directory ngspice/simple_por/.
Added new directory ngspice/digital_pll/ containing simulation testbenches for
the digital PLL and trimmable ring oscillator. Added qflow directories for
both; this was done only to get a valid xspice file for the controller and
a valid SPICE netlist for the ring oscillator.
diff --git a/qflow/ring_osc2x13/project_vars.sh b/qflow/ring_osc2x13/project_vars.sh
new file mode 100644
index 0000000..5010715
--- /dev/null
+++ b/qflow/ring_osc2x13/project_vars.sh
@@ -0,0 +1,66 @@
+#!/bin/tcsh -f
+#------------------------------------------------------------
+# project variables for project ~/gits/caravel/qflow/ring_osc2x13
+#------------------------------------------------------------
+
+# Flow options:
+# -------------------------------------------
+# set synthesis_tool = yosys
+# set placement_tool = graywolf
+# set sta_tool = vesta
+# set router_tool = qrouter
+# set migrate_tool = magic_db
+# set lvs_tool = netgen_lvs
+# set drc_tool = magic_drc
+# set gds_tool = magic_gds
+# set display_tool = magic_view
+
+# Synthesis command options:
+# -------------------------------------------
+# set hard_macros =
+# set yosys_options =
+# set yosys_script =
+# set yosys_debug =
+# set abc_script =
+# set nobuffers =
+# set inbuffers =
+# set postproc_options = "-anchors"
+# set xspice_options = "-io_time=500p -time=50p -idelay=5p -odelay=50p -cload=250f"
+# set fill_ratios = "0,70,10,20"
+# set nofanout =
+# set fanout_options = "-l 200 -c 20"
+# set source_file_list =
+# set is_system_verilog =
+
+# Placement command options:
+# -------------------------------------------
+# set initial_density =
+# set graywolf_options =
+# set addspacers_options = "-stripe 2.5 50.0 PG"
+
+# Router command options:
+# -------------------------------------------
+# set route_show =
+# set route_layers = "5"
+# set via_use =
+# set via_stacks =
+# set qrouter_options =
+# set qrouter_nocleanup =
+
+# STA command options:
+# -------------------------------------------
+
+# Minimum period of the clock use "--period value" (value in ps)
+# set opensta_options =
+# set vesta_options =
+
+# Other options:
+# -------------------------------------------
+# set migrate_options =
+# set lef_options =
+# set drc_gdsview =
+# set drc_options =
+# set gds_options =
+
+#------------------------------------------------------------
+
