Index: trunk/doc-rnd/devlog/20150830b_back_ann.html
===================================================================
--- trunk/doc-rnd/devlog/20150830b_back_ann.html (revision 909)
+++ trunk/doc-rnd/devlog/20150830b_back_ann.html (revision 910)
@@ -37,9 +37,9 @@
netlist in pcb from whatever gnetlist produced" approach would not work.
An alternative is to keep the netlist as-is, and maintain a separate list of
-changes. The form proposed hereby is a table of "operation,net,pinID" or
-"operation,net". Operation is one of "del_conn", "add_conn", "del_net" and
-"add_net". The table is called the netlist patch.
+changes. The form proposed hereby is a table of "operation,pinID,net" or
+"operation,args...". Netlist operation is one of "del_conn", "add_conn" and "net_info". The table is called the netlist patch.
For example assume two components with pins A1, A2 and B1, B2, with connections
n1=A1-B1 and n2=A2-B2. While routing the designer decides changing them to
@@ -46,11 +46,11 @@
n1=A1-B2 and n2=A2-B1 would be easier and is acceptable by the design. The
table of changes would contain this:
- | op | net | pinID
- |
|---|
| del_conn | n1 | B1
- |
| del_conn | n2 | B2
- |
| add_conn | n1 | B2
- |
| add_conn | n2 | B1
+ |
| op | pinID | net
+ |
|---|
| del_conn | B1 | n1
+ |
| del_conn | B2 | n2
+ |
| add_conn | B2 | n1
+ |
| add_conn | B1 | n2
|
The first two lines would remove pins B1 and B2 from n1 and n2. The last
two would put them back, swapped. New nets could be created or unused nets
@@ -63,17 +63,17 @@
The table would be normalized after operations. For example:
- | op | net | pinID
- |
|---|
| del_conn | n1 | B1
- |
| add_conn | n2 | B1
- |
| add_conn | n3 | B1
- |
| del_conn | n2 | B1
+ |
| op | pinID | net
+ |
|---|
| del_conn | B1 | n1
+ |
| add_conn | B1 | n2
+ |
| add_conn | B1 | n3
+ |
| del_conn | B1 | n2
|
would be reduced to
- | op | net | pinID
- |
|---|
| del_conn | n1 | B1
- |
| add_conn | n3 | B1
+ |
| op | pinID | net
+ |
|---|
| del_conn | B1 | n1
+ |
| add_conn | B1 | n3
|
Simple linear crawls on the table seems sufficient: it is expected that
pcb designers will make netlist modifications rarely and they will back
@@ -93,6 +93,9 @@
case the first row of the table is deleted, as B1 is already removed from n1,
but pcb-rnd has no chance to decide if netlist adding B1 to n3 should affect
the table adding B1 to n2, so that rule is kept.
+
+net_info is used to describe the original members of a net, in
+the state they were before any change on the netlist occured.
Support in pcb-rnd: GUI
A trivial idea is to extend the netlist window so that pins can be moved in
@@ -107,9 +110,9 @@
Using the above example (n1=A1-B1 and n2=A2-B2 changed to n1=A1-B2 and n2=A2-B1),
I believe the user would:
- | action | screenshot
- |
|---|
| 
- |
| | 
+ |
| action | screenshot | patch list after the actions
+ |
|---|
| | (empty)
+ |
| | | (empty)
|
- then realize it's very hard to connect A2 to B2 while the previous connection is there
@@ -117,6 +120,7 @@
- and connect A1 to B2
- which would cause shorts
| 
+ | (empty)
|
- then he would use the "approve netlist change" hotkey/action on the network;
@@ -125,6 +129,13 @@
of the new connection there'd be a rat between A1 and A2 or B1 and B2 too
(all 4 pins connected together on the patched netlist at the moment!)
| 
+ |
+
+net_info n1 A1 B1
+net_info n2 A2 B2
+del_conn B1 n1
+add_conn B1 n2
+
|
- the user would then use an action (maybe the same one?) on the rat line
@@ -132,11 +143,31 @@
would add a patch to remove the A1-B1 connection
- the same thing would need to happen to the A2-B2 rat
| 
+ |
+
+net_info n1 A1 B1
+net_info n2 A2 B2
+del_conn B1 n1
+add_conn B1 n2
+del_conn B2 n2
+
+
+
|
- the user then would connect A2 to B1, which again is a short
| 
|
- the user would approve it as a new connection
- we have exactly 2 del_conn and 2 add_conn patches.
| 
+ |
+
+net_info n1 A1 B1
+net_info n2 A2 B2
+del_conn B1 n1
+add_conn B1 n2
+del_conn B2 n2
+add_conn B2 n1
+
+
|
An experienced user may think a few steps in advance and
chose to first remove the A1-B1 and A2-B2 rats and then create the A1-B2
@@ -234,8 +265,8 @@
done in pcb-rnd as described above.
The netlist patch generated for this single change by pcb-rnd would be:
- del_conn netname1 U1-1
- add_conn netname2 U1-1
+del_conn netname1 U1-1
+add_conn netname2 U1-1
the user may need to load the netlist patch in ghscem
In gschem there would be an indication that highlights any U1-1 pin or
@@ -258,7 +289,7 @@
more appropriate. He does the change in pcb-rnd.
pcb-rnd emits the following netlist patch for this:
- change_attrib U1 footprint=DIP(8) footprint=SO(8)
+change_attrib U1 footprint=DIP(8) footprint=SO(8)
(or it could be a del_attrib and add_attrib pair, like with connections)