Re: [PEDA] Auto Router Oddity
Stephen, See point 2 in the following kb item. Regards, Gyula Hegyesi Protel Knowledge Base Item - 1694 Logged: 3/30/1998 Revised:7/30/2001 Item categories: Autorouting Products affected: Protel 98 (All Versions);99 (All Versions); Operating systems affected: Windows 95;98;NT; Query: Why won't my board autoroute? Details: Sometimes when attempting to route a PCB file in Advanced Route, it can remain in the Initializing shape based route pass, or stop after Initializing. Answer: Use the following points to help identify why the board will not route; 1. Check that the PCB outline has been placed on the Keep Out Layer and not a Mechanical Layer. (For example, make sure that the Keep Out Layer is used instead of Mechanical Layer 1 as these 2 layers are the same color). 2. Insure that there is some outline on the Keep Out Layer. It has been found that the outline need not be completely closed, i.e. the corners do not need to touch. Arcs are not supported in board outline on the Keepout Layer. They are ignored. This is the reason why a board outline defined by a full arc will not initialize and start routing. In the case where tracks and arcs make up the board outline, the arcs get ignored and in effect a straight line is used to close up the gap of where the arc was placed. Generally, in place of the arc there is a straight line assumed from and to the nearby tracks on the Keep out layer. 3. Enable all the layers that are needed for routing the PCB in the Design Rule » Routing Layers setup. When setting up the routing layers you will need to keep in mind that the present autorouter requires either the top or bottom layer to be enabled in the Routing Layers setup. Otherwise you will receive the error message Design Rule Error: no pads defined on any layers. Pressing OK will close down this error and it will appear to want to start autorouting by prompting you to change the routing grid to 0mil. The end result is that the autorouter will be unable to initialize. 4. Avoid using net names with hyphens, spaces; characters other than the alphabet and numbers. 5. Maintain net names less than 10 characters. 6. Maintain pad designator names to 4 characters or less. 7. In Route 98, the router requires all parts of the board to be within a 32x32 inch region from the absolute workspace origin (not the set-able current origin). Note that the coordinates on the Status bar display the distance from the set-able current origin, so if you are not sure reset the origin. To reset the origin select Edit » Origin » Reset from the menus. In Route 99, the autorouter workspace is the same as the PCB workspace of 100x100 inch. 8. Avoid placing any polygons prior to routing. This includes split planes. 9. Polygons that are placed on the top or bottom overlay, or mechanical layers can prevent the autorouter from initializing and routing the PCB. This includes polygons that have been included in a footprint. You will need to edit the footprint and remove the polygon. 10. Check for polygons that are not visible. See Item 2434 for more details. 11. Avoid placing components on a grid smaller than 1mil. It is recommended that components be aligned to a 5mil grid. On high density PCBs, too many components, tracks and other primitives placed on fractional grids (that is less than 1mil grid) can cause the autorouter to find too many contentions. A message similar to One or too many contentions have been found.. The only remedy to this situation is to place components and any routed tracks on at least 1mil grid. 12. Avoid placing tracks, arcs, etc on the multilayer. The router fails to start when it finds primitives other than pads/vias on the multilayer within the keepout region. If you move these primitives temporarily outside the keepout region the autorouter will start to route the PCB. 13. Check the PCB against the maximum capabilities of the autorouter listed in Item 2214. This includes the number of components, pins, etc. Brad Velander wrote: Gary, I don't use the autorouter at all but I have to ask about your multilayer lines. Were any segments of these lines actually arcs? Like at the ends of your slot? The Protel autorouter does not like arcs, I don't know the exact connotation of that statement but on numerous occasions the comment has been raised by those that do use the autorouter. Commonly it is in regards to the board outline (possibly that's on the keepout layer). Brad Velander, Lead PCB Designer, Norsat International Inc., #300 - 4401 Still Creek Dr., Burnaby, B.C., V5C 6G9. Tel. (604) 292-9089 direct Fax (604) 292-9010 website www.norsat.com -Original Message- From: G. Allbee
Re: [PEDA] Unable to Initialize
Hi Dave, I seem to have to repost this again and again... Gyula ** Protel Knowledge Base Item - 1694 Logged: 3/30/1998 Revised:7/30/2001 Item categories: Autorouting Products affected: Protel 98 (All Versions);99 (All Versions); Operating systems affected: Windows 95;98;NT; Query: Why won't my board autoroute? Details: Sometimes when attempting to route a PCB file in Advanced Route, it can remain in the Initializing shape based route pass, or stop after Initializing. Answer: Use the following points to help identify why the board will not route; 1. Check that the PCB outline has been placed on the Keep Out Layer and not a Mechanical Layer. (For example, make sure that the Keep Out Layer is used instead of Mechanical Layer 1 as these 2 layers are the same color). 2. Insure that there is some outline on the Keep Out Layer. It has been found that the outline need not be completely closed, i.e. the corners do not need to touch. Arcs are not supported in board outline on the Keepout Layer. They are ignored. This is the reason why a board outline defined by a full arc will not initialize and start routing. In the case where tracks and arcs make up the board outline, the arcs get ignored and in effect a straight line is used to close up the gap of where the arc was placed. Generally, in place of the arc there is a straight line assumed from and to the nearby tracks on the Keep out layer. 3. Enable all the layers that are needed for routing the PCB in the Design Rule » Routing Layers setup. When setting up the routing layers you will need to keep in mind that the present autorouter requires either the top or bottom layer to be enabled in the Routing Layers setup. Otherwise you will receive the error message Design Rule Error: no pads defined on any layers. Pressing OK will close down this error and it will appear to want to start autorouting by prompting you to change the routing grid to 0mil. The end result is that the autorouter will be unable to initialize. 4. Avoid using net names with hyphens, spaces; characters other than the alphabet and numbers. 5. Maintain net names less than 10 characters. 6. Maintain pad designator names to 4 characters or less. 7. In Route 98, the router requires all parts of the board to be within a 32x32 inch region from the absolute workspace origin (not the set-able current origin). Note that the coordinates on the Status bar display the distance from the set-able current origin, so if you are not sure reset the origin. To reset the origin select Edit » Origin » Reset from the menus. In Route 99, the autorouter workspace is the same as the PCB workspace of 100x100 inch. 8. Avoid placing any polygons prior to routing. This includes split planes. 9. Polygons that are placed on the top or bottom overlay, or mechanical layers can prevent the autorouter from initializing and routing the PCB. This includes polygons that have been included in a footprint. You will need to edit the footprint and remove the polygon. 10. Check for polygons that are not visible. See Item 2434 for more details. 11. Avoid placing components on a grid smaller than 1mil. It is recommended that components be aligned to a 5mil grid. On high density PCBs, too many components, tracks and other primitives placed on fractional grids (that is less than 1mil grid) can cause the autorouter to find too many contentions. A message similar to One or too many contentions have been found.. The only remedy to this situation is to place components and any routed tracks on at least 1mil grid. 12. Avoid placing tracks, arcs, etc on the multilayer. The router fails to start when it finds primitives other than pads/vias on the multilayer within the keepout region. If you move these primitives temporarily outside the keepout region the autorouter will start to route the PCB. 13. Check the PCB against the maximum capabilities of the autorouter listed in Item 2214. This includes the number of components, pins, etc. Sanders, Dave wrote: Has anyone out there ever experienced the wonderfully informative message Unable to Initialize when trying to autoroute. I really need some hints on what can cause this error. The Protel knowledge base comes up with nothing. I am running 99SE SP6 on a Win NT4 machine, designing a 6 layer board (4 sig. 2 pwr.), not particularly dense. Dave Sanders * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * To post a message: mailto:[EMAIL PROTECTED] * * To leave this list visit: * http://www.techservinc.com/protelusers/leave.html * * Contact the list manager: * mailto:[EMAIL PROTECTED] * * Forum Guidelines Rules: * http://www.techservinc.com/protelusers/forumrules.html * *
