On Fri, Apr 13, 2012 at 02:48:43PM +0200, Rob Clarke wrote: [...] > The TOD clock on the CIA's has a control bit which indicates whether the > clock signal is 50 or 60 hz. I could not for the life of me remember how > this gets set by the Kernal. The CBM-II's had a jumper on one of the TPI's > but AFAIK, the only jumper on the 64 boards was only for the clock > divider, and not hooked up to any of the control ports. As the 64 kernal > was region agnostic, how did it set the 50/60hz control? Anyway, frequency of the AC input is not so exact sometimes, so TOD can be quite un-precise. I was thinking some years ago to try to use another input signal for the CIAs which is more stable, so TOD will be more "usable". This can be interesting for me now, as I want to interface some SPI devices including SD card and a real-time clock chip, but I feel more "compatible" if softwares can use TOD, just it would be initialized from the real time clock ... Message was sent through the cbm-hackers mailing listReceived on 2012-04-13 13:00:59
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