5 ms·
A piece of equipment I worked on in the USAF had 512 bytes of core memory. If I recall correctly, it was constructed of nine planes of 512 cores each, where you
by chiph 10y ago
A piece of equipment I worked on in the USAF had 512 bytes of core memory. If I recall correctly, it was constructed of nine planes of 512 cores each, where you had 8 data planes (bits) and one parity plane. It dated from the Vietnam war as a joint Army-Air Force project, and was being phased out in the mid-80's with a new microprocessor-based system.
I once had to replace a defective memory assembly -- the end of messages in the system were indicated with 4 N's in the first few columns ("NNNN") and one of the cores went bad so the N in that column was never recognized (the other characters in that column were munged too), and so the message never ended. Over a day with an oscilloscope to find that one bad core and convince the NCOIC that I was right... I didn't have a microscope, but to the naked eye the core looked fine. It just wasn't flipping like it should have.
- Fjolsvith 10y agoWas that the 490L Overseas Autovon? I went to school for that phone switch in 1987 and was in the last class before they decommissioned it for the DOD. It had a core memory when it was initially deployed.
- chiph 10y agoThis was DSTE [0] connected to AUTODIN [1]. AUTOVON [2] was still around -- I only heard of Flash Override being used once, and the recipient of the call was sent back stateside shortly thereafter... We had a Siemens phone switch at that base, probably because AT&Ts 5ESS wasn't available at contract-signing time. At a later base I was at, they were installing the then-new X.400 system [3]. It didn't last long, as SMTP ate it's lunch. Which is funny, as I got to watch an IMP [4] get installed by the BBN [5] contractor that same year. [0] http://www.1882nd.com/images/DSTE.jpg http://www.1882nd.com/images/DSTE.jpg [1] https://en.wikipedia.org/wiki/Automatic_Digital_Network https://en.wikipedia.org/wiki/Automatic_Digital_Network [2] https://en.wikipedia.org/wiki/Autovon https://en.wikipedia.org/wiki/Autovon [3] https://en.wikipedia.org/wiki/Defense_Message_System https://en.wikipedia.org/wiki/Defense_Message_System [4] https://en.wikipedia.org/wiki/Interface_Message_Processor https://en.wikipedia.org/wiki/Interface_Message_Processor [5] https://en.wikipedia.org/wiki/BBN_Technologies https://en.wikipedia.org/wiki/BBN_Technologies