Thursday, February 12, 2015

Uploading DMS V2R12 cards, starting shed wiring

SHARING OF 1130 CARD DECKS

I spent a bit of time cleaning up the COBOL files, then moved on to read in and upload the operating system files to load DMS V2 R12, the latest that was made for the 1130 systems. Here I ran into card damage, which was unavoidable as we removed the cards from their original location in Kansas, because humidity had caused the cards to swell and become so wedged in their metal trays they couldn't be lifted out.

The only way that the crew could remove them to relieve some pressure was to pry some section of cards out of the tray, then redistribute them across more trays. This caused some damage to the sides of the card decks, with the most jammed trays holding the system load decks.

I have two sets of V2 R11 decks and only one V2 R12 deck. Each of the decks has a different section with damage to it. Here is an example of part of a V2 R11 deck, where the leading edge of the cards are so crushed that it is not possible to feed it through the reader.

Leading edge damage on card deck, rendering it unreadable
My prime target, the V2 R12 deck, has a damaged section but most of the damage is on the trailing edge, which I could straighten enough to avoid jamming. It did read well but there is a small portion with some front edge damage. I will have to feed these through one card at a time.
Trailing edge damage, but cards were able to be read successfully
Some leading edge problems, but can be carefully smoothed and individually read

Preserving historical computing information entails handling problems like these, which at worst case might require punching a duplicate of each card on the keypunch.

DATACENTER SHED CONSTRUCTION

I did some hunting and found a conduit with plenty of spare room, which solves the issue of having to open the wall inside my den to wire in the new EMT that will carry the power to my outdoor outlet box. I should be able to snake my new wire through the conduit and bring it out where I want to place the outlet box. The one puzzle to solve is how to insert the offshoot into the wire path without breaking the existing wires that run all the way through the house.

I made a run over to Orchard Supply Hardware since my newest order with Lowes appears to be stuck in the same groove - probably unlaterally cancelled by the store due to one item being out of stock, but that status never communicated to me. Further, the 800 number customer service sees the order as being processed (same as I see on the web site) which I am sure will persist for many days until it disappears mysteriously.

I began to drill and tap a heatsink for the 100W LED light array, but the cheap tap I bought didn't last more than two holes, in large part because the handle I used from a Harbor Freight tap/die set was so shoddily made that one of the two threaded handles wouldn't thread into the gripping block. With one handle falling out, it was hard to apply pure rotation, leading to the stress of the tape (which was American Vermont, a brand with somewhat higher quality control standards even if the taps come from the same factory). I am not in the mood to drive 25 minutes roundtrip just to buy a second tap, so this sits on the shelf until tomorrow or the weekend.

I do have almost everything I need to begin installing the outdoor outlet and the wiring (with cord to plug into the outlet) inside the shed. It will be sunny and in the mid 70s for the next five days, which is appropriate for doing the wiring and shed completion. 

8 comments:

  1. Could you dup the cards on a keypunch by feeding them in trailing edge first?

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  2. ... or scan them on a flatbed scanner?

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  3. or use the existing source decks supplied with the 1130 simulator to re-punch the missing DMS build cards on the 029 when you get your interface working!

    FYI there was a final DMS PTF (R2V13) which exists as scanned card files here: http://www.cosecans.ch/cosecans/IBM1130FinalPTF/ . I don't know if they are complete but I believe most disk packs had DMS R2V12.

    - Peter

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    1. That is definitely the 'gold standard' source of the decks, but need my 1442 punch working or my SAC interface emulating a punch with link to a PC, which will be a while.
      Thanks for the pointer to the PTF that would create V2R13 -I will see if I can assemble those and put it into a V13 update sequence for those who want to update their dms disks, both real and 1130 simulator oriented, to the latest version.

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  4. Those are among the ways to capture card data if I can't get it to read on the Documation reader - although duplicating binary cards on a keypunch is harmful to the machine if there are more than three holes punched in a column. It can damage the shifting plate that would print on the top of the card, even if the print switch is turned off, as well as stressing the punches whose design is for no more than 3 holes at a time. Instead, these should be copied manually, using the multipunch key on the 029, then checked against the original to ensure no holes were missed or added.

    The time to manipulate and individually read a card is still lower with the card reader than with the other methods, thus my preferred approach, but these are examples of backup methods for any card that just can't be read on the Documation.

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  5. Scan, yeah, has anyone ever done any work toward reading cards by scanning them optically? In a flatbed scanner with a black background, you wouldn't need a high-res image, just 100dpi would be plenty. To someone like me who's never written any image-processing code, it seems like a relatively simple job to recognize the boundary of a card, divide its area proportionally into the 12 rows and 80 columns, and look for black spots. Well, yeah, but if the card is a bit skewed in the image... maybe not so simple. I'll let somebody else bell that cat.

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    1. I have read mention of this a few times but don't know of a completed mechanism someone is using. Makes a lot of sense, rather than moving the card past a small set of light detectors, use the entire image of the card and some image processing.
      It wouldn't seem hard to do edge detection to figure out the card size and orientation, then scale and rotate the image to a normalized image for which the column/row positions are pre-calculated for ease of hole capture.

      Minor detail is the printing or coloring of cards, which might interfere a bit with hole detection. The simplest case is an all white/light card and a dark background under the card, but there were a huge number of printed cardstock variations, some of which conceptually might cause a false positive for a hole. May not be a practical problem, but I haven't done the design work to know that yet.

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  6. Like you I've heard of this being done, which is why I suggested it, but unfortunately I don't have any specifics either.

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