     $A0-$A2/160-162:   Real-time jiffy Clock

       Updated by IRQ Interrupt approx every 1/60 of Second

       Update Routine is at $F69B

    Kernal-Reference:

     BIT $00A0   : $AFE8
     INC $A0     : $F6A5
     LDA $A0     : $F6B0
     LDY $A0     : $F6E2
     STX $A0     : $F6B6
     STY $A0     : $F6E9

     CMP $A1     : $E4E7
     INC $A1     : $F6A1
     LDA $A1     : $F6AC $F761
     LDX $A1     : $F6E0
     STX $A1     : $F6B8 $F6E7

     BIT $00A2   : $A908
     INC $A2     : $F69D
     LDA $A2     : $F6DE
     STA $A2     : $F6E5
     STX $A2     : $F6BA