tag:blogger.com,1999:blog-8869371566442567811.post4952631855828687233..comments2024-03-27T23:23:05.548-07:00Comments on Rescue 1130: 2014 Pickup of an IBM 1130 System and More: Keypunch now reading except it misses column 1 of each card - more progress on SAC interfaceCarl Claunchhttp://www.blogger.com/profile/00359841432891565909noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-8869371566442567811.post-71054845310643392772014-11-10T20:54:32.405-08:002014-11-10T20:54:32.405-08:00Yes, David, you are on the right track. When you u...Yes, David, you are on the right track. When you use the DUP key, it is called a manual duplicate (contrasted to auto DUP driven by the program drum). Manual dup is done with two punch cycles per column, the first is called a 'dummy punch cycle' which rotates the mechanism to raise the sensing pins to read the holes in the 'master' card. Those holes trigger the solenoids for the holes to be punched, then a relay that is latched blocks the punch cycle from ending so it starts a second cycle where it really punches the holes in the card. The second cycle is when the card moves to the next column (just before the holes are punched).<br /><br />All this is done by sequencing of at least four relays that orchestrate these steps. <br /><br />When a card is first registered in the keypunch, the card that will have holes punched (the 'detail card') is sitting at column 0 and simultaneously if there is a card in the master station (that will be duplicated) it is sitting at column 1. The cards move in unison but are not on the same column number.<br /><br />When a key is pressed and holes punched, the first step is to release the escapement to move both cards forward one column. Once that ends the punch cycle begins, driving the punches through the card stock. This is why I wasn't reading the first column - the master card will be moved to column 2 while the detail card advances to column 1, and only then does the punch cycle run which drives the sensing pins. This is why in normal punching, column 1 will never be sensed. <br /><br />I found a way to trigger a punch cycle without activating any of the row magnets and without triggering a movement first. That makes it the same as a dummy punch cycle, so it does a sense of column 1 of the master card and leaves the detail card at column zero. Once I have the data, I revert to normal punching for the rest of teh card, where each character causes a move forward then punches the holes.<br />Carl Claunchhttps://www.blogger.com/profile/00359841432891565909noreply@blogger.comtag:blogger.com,1999:blog-8869371566442567811.post-82391146940658958902014-11-10T20:27:17.171-08:002014-11-10T20:27:17.171-08:00Check the schematic for the operation of the DUP k...Check the schematic for the operation of the DUP key. Surely the KP is capable of dup'ing a field starting in column 1? So, it has to be able to both sense column 1 and punch column 1 during a DUP cycle. Oh! Maybe that means that on a DUP it does some kind of overlap? On the first column of the DUP field, it just does a sense, no punch (storing the sensed values somewhere, in magnets or latches); and on succeeding cycles it punches the prior column while sensing the next one. That would probably explain why you can't pick up column 1 but you can read 2 and so on. So look at how the DUP works and I bet there will be some provision for a no-punch, sense-only cycle.David Cortesihttps://www.blogger.com/profile/06760661115101469280noreply@blogger.com