10 ORG &H9000
20 CALL &HC3
30 RET
40 IN A,(&hA8)
50 LD B,A
60 SRL A
70 SRL A
80 OR B
90 OUT (&HA8),A
100 XOR A
110 LD HL,&HFFFF
120 LD (HL),0
130 LD HL,&H9000
140 LD DE,&H4000
150 LD B,4
160 LOOP: LD A,(HL)
170 LD (DE),A
180 INC HL
190 INC DE
200 DJNZ LOOP
210 CALL &H4000
220 IN A,(&HA8)
230 AND &B1111000
240 OUT (&HA8),A
250 RET
