Atari 400 Technical Reference Manual page 355

ERR LINE ADDR B1 B2 B3 B4
DISPLAY HANDLER -- 10-30-78 --
DISPLC PAGE 94
4094
. PAGE
4095
4096
4097
i
BEGIN DISPLAY HANDLER OPEN PROCESSING
4098
4099 F3F6 AS 2B DOPEN: LDA
ICAX2Z iGET AUX 2 BYTE
4100
F3F8 29 OF AND
#$F
4101 F3FA DO 08
BNE OPNCOM
i IF MODE ZERO, CLEAR ICAX1Z
4102 F3FC AS 2A
EOPEN: LDA ICAX1Z
iCLEAR "CLR INHIBIT" AND "MXD MODE" BITS
4103 F3FE 29 OF
AND
#$F
4104 F400 852A
STA ICAX1Z
4105 F402 A9 00
LDA #0
4106 F404 85 57
OPNCOM: STA DINDEX
4107 F406 A9 EO LOA
#$EO
i
INITIALIZE GLOBAL VB LANK RAM
4108 F408 80 F4 02
STA CHBAS
4109 F40B A9 02 LDA
#2
4110 F40D 8D F3 02
STA CHACT
4111 F410 8D 2F 02
STA SDMCTL
iTURN OFF DMA NEXT VB LANK
4112 F413 A9 01
LDA #SUCCES
4113 F415 85 4C
STA DSTAT iCLEAR STATUS
4114 F417 A9 CO LDA
#$CO
i
DO IRGEN
4115 F419 05 10 ORA
POKMSK
4116
F41B 85 10 STA POKMSK
4117
F41D
8D OE D2
STA IRGEN
4118
F420 A9 00 LDA
#0
4119 F422 80 93 02
STA TINDEX
iTEXT INDEX MUST ALWAYS BE 0
4120 F425 85 64
STA ADRESS
4121 F427 85 7B
STA SWPFLG
4122 F429 8D FO 02 STA
CRSINH iTURN CURSOR ON AT OPEN
4123 F42C AO OE LDY
#14 iCLEAR TAB STOPS
4124 F42E A9 01 LDA
#1 i INIT TAB STOPS TO EVERY 8 CHARACTERS
4125
F430 99 A3 02 CLRTBS: STA TABMAP,Y
4126 F433 88
DEY
4127 F434 10 FA
BPL CLRTBS
4128 F436 A2 04
LDX #4 iLOAD COLOR REGISTERS
4129 F438 BD C1 FE
DOPEN8: LDA COLRTB,X
4130 F43B 9D C4 02 STA
COLORO,X
4131 F43E CA
DEX
4132 F43F 10 F7 BPL
DOPEN8
4133 F441 A4 6A
LDY RAMTOP
iDO TXTMSC=$2C40 (IF MEMTOP=3000)
4134 F443 88 DEY
4135 F444 8C 95 02 STY
TXTMSC+1
4136 F447 A9 60 LDA
#$60
4137 F449 8D 94 02 STA
TXTMSC
4138
F44C A6 57 LDX DINDEX
4139
F44E BD 69 FE LDA ANCONV, X
iCONVERT IT TO ANTIC CODE
4140
F451
DO 04
BNE DOPENA
; IF ZERO, IT IS ILLEGAL
4141 F453 A9 91
OPNERR: LOA #BADMOD ; SET ERROR STATUS
4142
F455
85 4C
STA DSTAT
4143 F457 85 51
DOPENA: STA HOLD1
4144 F459 AS 6A LDA RAMTOP
iSET UP AN INDIRECT POINTER
4145 F45B 85 65
STA ADRESS+1
4146 F45D BC 45 FE LDY
ALOCAT,X iALLOCATE N BLOCKS OF 40 BYTES
4147 F460 A9 28 DOPENI : LDA
#40