CNC/NC (Was HP91XX Controllers)

Most all CNC controls today have Ethernet interfaces, and have means (FTP or CIFS access to files on a fileserver share) to copy programs to the control. Many controls nowadays also have USB ports, so you can put program(s) on thumb drives and copy them onto the control that way. Earlier controls had RS-232 ports. I wrote a system on a PC running FreeBSD Linux using Perl (a very early version) that would send and receive programs to all of the controls in the shop over RS-232. I used a SCSI terminal server box from Central Data that hooked up to the PC over a SCSI channel, and provided 16 RS-232 serial ports that went out to all of the machines. Amazingly enough, this thing is still in service (in a shop environment) after over 15 years, providing an easy way to load programs on some of the older controls. I remember the first "NC" machine (no computer inside, so it wasn't CNC) that my Dad's shop had. It was a Rambaudi Vertical Mill. The control was made by Wang Laboratories. It used paper tape, in EIA code. A Friden Flexowriter was used to prepare tapes. The X, Y and Z motors weren't steppers, they were servos with resolvers attached to make a closed loop system, a very curious mix of analog and digital. The control was all transistorized...no ICs. For a project for school, my Dad gave me blueprints for a part that they had been contracted to make, and I wrote the program (very simple drilling/tapping on a flat block of steel) to make the part. It worked first time. I think I was in 5th or 6th grade, can't remember for sure). I remember one machine, it was a lathe, that had a control that had an industrial PDP 8/e in it, with blinky lights and switches (red and blue). I was really upset with my Dad when the machine was taken out of the commission (it simply wore out and wasn't worth repairing), and they called a scrapper to come get it, control and all. It is truly amazing how far machining technology has come in a relatively short time. Rick Bensene The Old Calculator Museum http://oldcalculatormuseum.com