On Thu, 28 May 2009 15:35:28 -0400, Clark Kidd wrote: > >As I remember, there were three "control" rows at the top of the card (12, 11, >0) and then 9 "data" rows (1-9) under those. So each possible column would >contain up to 12 rows that could be punched: > And the 8-row seemed to function almost as an auxiliary zone row.
> But how about if there were too MANY holes? I remember they made some small > silver adhesive squares that could be placed over a hole so that it wouldn't > be read. Or simply poke a chad (available on eBay or any garage sale in Florida) back in the hole and van der Waals forces would retain it long enough to DUP the card. (026 used brushes, not microswitches, right?) Seymour Cray was reported to punch binary cards de novo. CDC made a card reader (405?) that read columnwise. I once made an 81 column card by applying friction with a thumb on an 026 keypunch while punching. CDC reader read the first 80 columns successfully. I forget what, if any error it reported on the 81st. -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
