Mel, with your help I now have something I can work with

Code:
AlarmH1=(RTCHour>>4)
AlarmH1=(AlarmH1&$03)*10
AlarmH1=AlarmH1+(RTCHour&$0F)

AlarmM1=(RTCMin>>4)
AlarmM1=(AlarmM1&$07)*10
AlarmM1=AlarmM1+(RTCMin&$0F)

AlarmH2=(RTCHour>>4)
AlarmH2=(AlarmH2&$03)*10
AlarmH2=AlarmH2+(RTCHour&$0F)

AlarmM2=(RTCMin>>4)
AlarmM2=(AlarmM2&$07)*10
AlarmM2=AlarmM2+(RTCMin&$0F)
    
AlarmHour1 = 19
Alarmmin1 =  07
AlarmHour2 = 19
AlarmMin2 = 09

	
	LCDOut ":",#(RTCMin>>4)&$0F,#RTCMin&$0F,":"
	LCDOut #(RTCSec>>4)&$0F,#RTCSec&$0F," "
    LCDOut $FE, $94,"H1M1= ",#AlarmH1,":",#AlarmM1," ",#AlarmH2,":",#AlarmM2
	LCDOut $FE, $D4,"set= ",#alarmhour1,":",#alarmmin1," ",#alarmhour2,":",#AlarmMin2 

If AlarmHour1=AlarmH1 and alarmmin1=AlarmM1 then
 HIGH PortD.7
 endif
if alarmhour2=AlarmH2 and AlarmMin2=alarmm2 then 
  LOW PortD.7
endif
Ignore the lcdout alarmm1 etc, that was just to view the values. Interestingly it shows 19:05 as 19:5, but works regardless.

Thanks to everyone who contributed (both on the board and via e-mail), especially Mel for taking so much trouble to explain things in layman terms