Technical information

Micro-KIM Users Manual
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CARD # LOC CODE CARD
931 1E51 30 02 BMI HEXTA1
932 1E53 69 07 ADC #$07 ALPHA HEX
933 1E55 69 30 HEXTA1 ADC #$30 DEC HEX
934 1E57 4C A0 1E JMP OUTCH PRINT CHAR
935 ;
936 ; GET 1 CHAR FROM TTY
937 ; CHAR IN A
938 ; X IS PRESERVED AND Y RETURNED = FF
939 ;
940 1E5A 86 FD GETCH STX TMPX SAVE X REG
941 1E5C A2 08 LDX #$08 SET UP 8-BIT CNT
942 1E5E A9 01 LDA #$01
943 1E60 2C 40 17 GET1 BIT SAD
944 1E63 D0 22 BNE GET6
945 1E65 30 F9 BMI GET1 WAIT FOR START BIT
946 1E67 20 D4 1E JSR DELAY DELAY 1 BIT
947 1E6A 20 EB 1E GET5 JSR DEHALF DELAY 1/2 BIT TIME
948 1E6D AD 40 17 GET2 LDA SAD GET 8 BITS
949 1E70 29 80 AND #$80 MASK OFF LOW ORDER BITS
950 1E72 46 FE LSR CHAR SHIFT RIGHT CHAR
951 1E74 05 FE ORA CHAR
952 1E76 85 FE STA CHAR
953 1E78 20 D4 1E JSR DELAY DELAY 1 BIT TIME
954 1E7B CA DEX
955 1E7C D0 EF BNE GET2 GET NEXT CHAR
956 1E7E 20 EB 1E JSR DEHALF EXIT THIS RTN
957 ;
958 1E81 A6 FD LDX TMPX
959 1E83 A5 FE LDA CHAR
960 1E85 2A ROL A SHIFT OFF PARITY
961 1E86 4A LSR A
962 1E87 60 GET6 RTS
963 ;
964 ; INITIALIZATION FOR SIGMA
965 ;
966 1E88 A2 01 INITS LDX #$01 SET KB MODE TO ADDR
967 1E8A 86 FF STX MODE
968 ;
969 1E8C A2 00 INIT1 LDX #$00
970 1E8E 8E 41 17 STX PADD FOR SIGMA USE SADD
971 1E91 A2 3F LDX #$3F
972 1E93 8E 43 17 STX PBDD FOR SIGMA USE SBDD
973 1E96 A2 07 LDX #$07 ENABLE DATA IN
974 1E98 8E 42 17 STX SBD OUTPUT
975 1E9B D8 CLD
976 1E9C 78 SEI
977 1E9D 60 RTS
978 ;
979 ; PRINT 1 CHAR CHAR IN A
980 ; X IS PRESERVED Y RETURNED = FF
981 ; OUTSP PRINTS 1 SPACE
982 ;
983 1E9E A9 20 OUTSP LDA #$20
984 1EA0 85 FE OUTCH STA CHAR
985 1EA2 86 FD STX TMPX
986 1EA4 20 D4 1E JSR DELAY 10/11 BIT CODE SYNC
987 1EA7 AD 42 17 LDA SBD START BIT
988 1EAA 29 FE AND #$FE