In Reply to: How to generate ncdrill in excellon format from allegro posted by Suganthi on 10/07/03 at 1:22 AM:
Here is an explanation of Excellon Drill Files:
Excellon is a manufacturer of CNC control systems for both drillers and routers. This company has been in the business of CNC control for many years. The Excellon Company can be best described as one of the pioneers Printed Circuit board drillers and routers.
The term "Excellon Drill File" is a bit of a misnomer, as the company's name has been attached to what should be simply described as an NC (numeric control) drill file. The most popular format of this data is Excellon's and is described in the following section. Although the term "Excellon" has been coined into the CAD environment don't let it confuse the issue of NC drill data.
There are many manufactures of drilling and routing equipment today. Most are fully compatible with Excellon's control codes. Some PCB vendors still require an older format known as EIA-Binary because their drill systems use an older paper tape reader system. Modern drilling equipment now uses the preferred ASCII drill formats and a PC or similar control computer interpret the ASCII files.
In Allegro you would select the "Manufacture" Icon from the tool-bar, then select "NC" and then "Drill Parameters". Set the parameters needed, one word of caution if you check the "Auto Tool Select" box then you will need to create a text file which sets up certain parameters. After setting up the drill parameters, you need to select "Manufacture", "NC", "Drill Tape" and execute the program.
Hope this info helps.