To quote the data sheet I have " A specific sequence of events must be followed for proper setting and reading of TOD. TOD is automatically stopped whenever a write to the Hours register occurs. The clock will not start again until after a write to the 10ths of seconds register. This assures TOD will always start at the desired time. Since a carry from one stage to the next can occur at any time with respect to a read operation, a latching function is included to keep all Time Of Day information constant during a read sequence. All Four TOD registers latch on a read of Hours and remain latched until after a read of 10ths of seconds. The TOD clock continues to count when the output registers are latched. If only one register is to be read, there is no carry problem and the register can be read "on the fly", provided that any read of Hours is followed by a read of 10ths of seconds to disable latching. " bogax - This message was sent through the cbm-hackers mailing list. To unsubscribe: echo unsubscribe | mail cbm-hackers-request@dot.tml.hut.fi.
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