![]() I still bump into it with CNC machines from time to time. There are people who really do need to continue with paper tape. You know, this project could have some application. Later when MSDOS PCs came into the picture, it was kind of fun to put programs on the tape and load them from it instead of floppy disk. Mylar paper tape can be read really, really fast! Second fastest is the black, oil saturated tape, and then came various papers after that. (I think it was supposed to work at 9600 both ways, but some of the tape we used was not the oil embedded type, or was mylar, and to make sure it would punch anything nicely, we lubed it on occasion and just ran slow enough to deal with any tape.) That thing worked at 4800 baud write, 9600 read. You would run programs from the cartridge system, which had indexes to help get specific programs off of it, do your thing, and generally output data, G-code and such using a combination of printer and paper tape, punched on the little puncher. They had a Tek storage display unit that used paper tape as it's I/O in tandem with cassette type cartridge units for faster, larger bulk storage. ![]() Many of the machines used paper tape due to their age, and the company being little and lean. I was at various machine stations using a Tandy pocket computer and BASIC programs to assist in the making of sheet metal parts and their layouts, doing statistical process control charts (hand plot after compute), etc. That shop was an interesting mix of the old and new. One had to smooth the ends a little, and use that really thin Scotch "transparent" type tape to make it reliable, but once setup, it could run for days. That's a long, skinny, rectangular compartment with a glass to see the tape in there, and some shaped sides to help smooth the entry and exit of the tape from the reader, into and out of the hopper. It ran in real time from paper tape, and was actually quite impressive! Heh, get this! A program loop actually was a loop! One fed the tape in, used the forward jog switch to feed it to the end, then taped the two ends together, leaving the length of the tape in a hopper. That's enough for a G-code, even a fairly complex one, and the up and coming G-code. It had only a buffer block of memory to work with. Some time back around '89 or maybe '90, I worked on an Amada PEGA class turret punch. It's still in wide use on older CNC machines of all kinds, lathe, punch, laser, mill. It was entirely electromechanical like a Selectric typewriter, with no electronics other than amplifiers to convert the RS-232 signals to something strong enough to operate a solenoid. This worked at 10 characters per second both punching and reading (with mechanical pins). The Teletype terminal also had a tape reader/writer, which the lab had to use before the high speed machines were acquired. They also had a high speed punch which was about a third as fast as the reader, and made an impressively loud noise as it punched. Then you hook the end on one spindle of a winder reel mounted in a machine that was originally designed as an electric pencil eraser, told it to spin, and WHIRRRRRR it would suck all that tape back up into a nice neat roll. ![]() The tape would end up in a big puddle on the floor of the lab, and the reader would catch the end so you wouldn't have to go hunting for it. When I was a kid we had an optical tape reader in my Dad's lab which could read an 8 kilobyte tape - about 4 inches in diameter - in 10 seconds. If you used photodiodes or phototransistors you would be able to read faster than you can pull the tape through by hand. The CdS photodetectors are seriously limiting your read speed. PS, not sure if this is the right forum for this, as I was going to place it into projects before it became robotics Hope you guys enjoy, and let me know if you have any questions!Addie I think eventually we may make some sort of card reader system for the hackerspace and use it to give out points - 5 points for coming, 10000 for cleaning - all redeemable for little erasers and oriental trading pencils! ![]() If you're interested, I've put the step by step of how I did it on: įor the thought process/daily updates I made during the project: Most folks tend to use it for crafts and scrapbooking but that skill is just not in my veins! So I decided to create paper tape/punch card and make a reader for it incorporating the Propeller BOE! We just finished a little project where we were required to use the Silhouette Portrait (CNC paper/fabric cutter). ![]()
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