****************************************************************************** ****************************************************************************** BIRD ID#: 78.1 ISSUE TITLE: Comment Line Length Limit REQUESTER: Lynne Green, Cadence Design Systems DATE SUBMITTED: September 6, 2002; December 10, 2002 DATE ACCEPTED BY IBIS OPEN FORUM: January 10, 2003 ****************************************************************************** ****************************************************************************** STATEMENT OF THE ISSUE: Currently, ibischk3 reports an error for comment lines that are longer than 80 characters. It is desirable to support longer comment lines in both IBIS 3.2 and IBIS 4.0. For example, when using a string for the full path to a file, the string can exceed the 80 character limit. Allowing the longer comment line would make this string fit on a single line, allowing EDA tools to more easily parse file names and paths. 120-character length limit would be needed to support BIRD 80 proposal. ****************************************************************************** STATEMENT OF THE RESOLVED SPECIFICATIONS: The line length limit should be 120 characters in IBIS 4.0. This is the same limit used in the IBIS Connector Specification draft. EDA tools would be required to read all 120 characters. Comment lines would also be limited to this length. Changes are noted in the relevant sections below by |** lines: | SECTION 3 | replace "80" with "120" in two places. | |** 4) A line of the file may have at most 120 characters, | | 10) The use of tab characters is legal, but they should be avoided as much | as possible. This is to eliminate possible complications that might | arise in situations when tab characters are automatically converted to | multiple spaces by text editing, file transferring and similar software. |** In cases like that, lines might become longer than 120 characters, | which is illegal in IBIS files. | ***************************************************************************** ANY OTHER BACKGROUND INFORMATION: Related increases in line length and string length limits, suggested by Barry Katz. 1) Remove 80 character limit on main lines, or increase it to 100 or 120 2) Double the number of characters in a model from 20 -> 30 or 40 3) Double the number of characters in a signal name from 20 -> 30 or 40 This would impact Sections 3, 5, and 6. #2 and #3 would require #1. ******************************************************************************