My first machine was an IBM 1620, but hey, at least we had an actual disk. A couple of 2311's.
To quote a fellow I used to consult for, two days' I had solved a particularly nasty programming problem for his company, "But what have you done for us lately?" On Thu, Oct 21, 2010 at 10:57 AM, RW <rwmailli...@googlemail.com> wrote: > On Thu, 21 Oct 2010 14:32:23 +0100 > Arthur Chance <free...@qeng-ho.org> wrote: > > > On 10/21/10 13:38, RW wrote: > > > On Wed, 20 Oct 2010 21:10:28 +0100 > > > Arthur Chance<free...@qeng-ho.org> wrote: > > > > > > > > >> 50s) had the experience of programming microcode on a machine by > > >> inserting brass slugs for 0s and ferrite slugs for 1s on a pin > > >> board. > > > > > > I wonder why it was brass/ferrite rather than brass/empty or > > > ferrite/empty. > > > > Dredging up physics unused for 30+ years, ferrite is ferromagnetic > > and intensifies magnetic fields so a coil of wire with ferrite inside > > is a massively bigger inductor then an empty coil. I vaguely remember > > that brass is slightly diamagnetic, but could be mistaken. If it is, > > then it would have the opposite effect and reduce the inductance, so > > you'd get a better difference in signal between brass/ferrite than > > air/ferrite. > > Possibly. I'm wondering if there might be three states, where the third > state is writable. > > > Air/brass would give very small differences in signal, > > I was thinking in that case it would be open/short circuit. > _______________________________________________ > firstname.lastname@example.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to " > freebsd-questions-unsubscr...@freebsd.org" > _______________________________________________ email@example.com mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"