Setting the Geneve clock
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The following routine can be used to reset the clock to a well-defined state, and then the date may be set using the MDOS command TIME.
* Resetting the clock to 24h mode * according to the MM58274C datasheet * Time must be set afterwards using the MDOS command TIME DEF START START LWPI >F000 LI R0,>0F00 MOVB R0,@>F130 // Write 0x0f into the control register SWPB R0 MOVB R0,@>F13F // Write 0x00 into the interrupt register LI R0,>0500 MOVB R0,@>F130 // Write 0x05 into the control register LI R0,>0100 LI R1,>F131 LI R2,14 LP01 MOVB R0,*R1+ // Write 0x01 to all registers DEC R2 JNE LP01 MOVB R0,@>F13F // Set 24h mode CLR R0 MOVB R0,@>F130 // Write 0x00 into the control register BLWP @0 END