ORG $007
- MPLX DISPLAY REFRESH -
             SEL RB1
             DIS TCNTI
             JTF 'NXI'
'NXI'        MOV R7,A
             MOV R0,#30     INIT DATA POINTER
             MOV R1,#01     INIT DIGIT DRIVE
'NEXT'       ANL P0,#00     TURN OFF ALL DIGIT
             MOV A,@R0      LOAD A DISPLAY DATA
             OUTL P1,A      WRITE DISPLAY DATA
             MOV A,R1       MOVE DIGIT DRIVE TO A
             OUTL BUS,A     AND OUTPUT
             RL A           DRIVE TO NEXT DIGIT
             MOV R1,A       AND SAVE IN R1
             MOV A,R0
             INC R0    
             MOVP3 A,@A     LOAD A WITH CONTRAST
             MOV T,A
             STRT T
'TOUT'       JTF 'CONT'
             JMP 'TOUT'
'CONT'       MOV A,R1
             JB5 'DONE'
             JMP 'NEXT'
'DONE'       ANL P0,#00
             MOV A,@R0
             MOV T,A
             EN TCNTI
             MOV A,R7
             STRT T
             RETR
-
ORG $330
- TIMER CONTRAST DATA -
,FD
,FD
,FE
,FE
,FE
END