; from gaithersburg md ibm pc bulletin board 19mar83 ; ; SUBTTL ROM BIOS DATA AREAS AND EQUATES ;-------------------------------- ; EQUATES ;-------------------------------- PORT_A EQU 60H ; 8255 PORT A ADDR PORT_B EQU 61H ; 8255 PORT B ADDR PORT_C EQU 62H ; 8255 PORT C ADDR CMD_PORT EQU 63H INTA00 EQU 20H ; 8259 PORT INTA01 EQU 21H ; 8259 PORT EOI EQU 20H TIMER EQU 40H TIM_CTL EQU 43H ; 8253 TIMER CONTROL PORT ADDR TIMER0 EQU 40H ; 8253 TIMER/CNTER 0 PORT ADDR TMINT EQU 01 ; TIMER 0 INTR RECVD MASK DMA08 EQU 08 ; DMA STATUS REG PORT ADDR DMA EQU 00 ; DMA CHANNEL 0 ADDRESS REG PORT ADDR MAX_PERIOD EQU 540H MIN_PERIOD EQU 410H KBD_IN EQU 60H ; KEYBOARD DATA IN ADDR PORT KBDINT EQU 02 ; KEYBOARD INTR MASK KB_DATA EQU 60H ; KEYBOARD SCAN CODE PORT KB_CTL EQU 61H ; CONTROL BITS FOR KEYBOARD SENSE DATA ;-------------------------------- ; 8088 INTERRUPT LOCATIONS ;-------------------------------- ABS0 SEGMENT AT 0 STG_LOC0 LABEL BYTE ORG 2*4 NMI_PTR LABEL WORD ORG 5*4 INTS_PTR LABEL WORD ORG 8*4 INT_ADDR LABEL WORD INT_PTR LABEL DWORD ORG 10H*4 VIDEO_INT LABEL WORD ORG 1DH*4 PARM_PTR LABEL DWORD ; POINTER TO VIDEO PARMS ORG 01EH*4 ; INTERRUPT 1EH DISK_PTR LABEL DWORD ORG 01FH*4 ; LOCATION OF POINTER EXT_PTR LABEL DWORD ; POINTER TO EXTENSION ORG 7C00H BOOT_LOCN LABEL FAR ABS0 ENDS PAGE ;-------------------------------- ; STACK -- USED DURING INITIALIZATION ONLY ;-------------------------------- STACK SEGMENT AT 30H DW 128 DUP(?) TOS LABEL WORD STACK ENDS ;-------------------------------- ; ROM BIOS DATA AREAS ;-------------------------------- DATA SEGMENT AT 40H RS232_BASE DW 4 DUP(?) ; ADDRESSES OF RS232 ADAPTERS PRINTER_BASE DW 4 DUP(?) ; ADDRESSES OF PRINTERS EQUIP_FLAG DW ? ; INSTALLED HARDWARE MFG_TST DB ? ; INITIALIZATION FLAG MEMORY_SIZE DW ? ; MEMORY SIZE IN K BYTES IO_RAM_SIZE DW ? ; MEMORY IN I/O CHANNEL PAGE ;------------------------------- ; KEYBOARD DATA AREAS ;------------------------------- KB_FLAG DB ? ;------ SHIFT FLAG EQUATES WITHIN KB_FLAG INS_STATE EQU 80H ; INSERT STATE IS ACTIVE CAPS_STATE EQU 40H ; CAPS LOCK STATE HAS BEEN TOGGLED NUM_STATE EQU 20H ; NUM LOCK STATE HAS BEEN TOGGLED SCROLL_STATE EQU 10H ; SCROLL LOCK STATE HAS BEEN TOGGLED ALT_STATE EQU 08H ; ALTERNATE SHIFT KEY DEPRESSED CTL_SHIFT EQU 04H ; CONTROL SHIFT KEY DEPRESSED LEFT_SHIFT EQU 02H ; LEFT SHIFT KEY DEPRESSED RIGHT_SHIFT EQU 01H ; RIGHT SHIFT KEY DEPRESSED ;------------------------------- KB_FLAG_1 DB ? ; SECOND BYTE OF KEYBOARD STATUS INS_SHIFT EQU 80H ; INSERT KEY IS DEPRESSED CAPS_SHIFT EQU 40H ; CAPS LOCK KEY IS DEPRESSED NUM_SHIFT EQU 20H ; NUM LOCK KEY IS DEPRESSED SCROLL_SHIFT EQU 10H ; SCROLL LOCK KEY IS DEPRESSED HOLD_STATE EQU 08H ; SUSPEND KEY HAS BEEN TOGGLED ;------------------------------- ALT_INPUT DB ? ; STORAGE FOR ALTERNATE KEYPAD ENTRY BUFFER_HEAD DW ? ; POINTER TO HEAD OF KEYBOARD BUFFER BUFFER_TAIL DW ? ; POINTER TO TAIL OF KEYBOARD BUFFER KB_BUFFER DW 16 DUP(?) ; ROOM FOR 15 ENTRIES KB_BUFFER_END LABEL WORD ;------ HEAD = TAIL INDICATES THAT THE BUFFER IS EMPTY NUM_KEY EQU 69 ; SCAN CODE FOR NUMBER LOCK SCROLL_KEY EQU 70 ; SCROLL LOCK KEY ALT_KEY EQU 56 ; ALTERNATE SHIFT KEY SCAN CODE CTL_KEY EQU 29 ; SCAN CODE FOR CONTROL KEY CAPS_KEY EQU 58 ; SCAN CODE FOR SHIFT LOCK LEFT_KEY EQU 42 ; SCAN CODE FOR LEFT SHIFT RIGHT_KEY EQU 54 ; SCAN CODE FOR RIGHT SHIFT INS_KEY EQU 82 ; SCAN CODE FOR INSERT KEY DEL_KEY EQU 83 ; SCAN CODE FOR DELETE KEY PAGE ;------------------------------- ; DISKETTE DATA AREAS ;------------------------------- SEEK_STATUS DB ? ; DRIVE RECALIBRATION STATUS ; BIT 3-0 = DRIVE 3-0 NEEDS RECAL BEFORE ; NEXT SEEK IF BIT IS = 0 INT_FLAG EQU 080H ; INTERRUPT OCCURRENCE FLAG MOTOR_STATUS DB ? ; MOTOR STATUS ; BIT 3-0 = DRIVE 3-0 IS CURRENTLY RUNNING ; BIT 7 = CURRENT OPERATION IS A WRITE, REQUIRES DELAY MOTOR_COUNT DB ? ; TIME OUT COUNTER FOR DRIVE TURN OFF MOTOR_WAIT EQU 37 ; TWO SECONDS OF COUNTS FOR MOTOR TURN OFF ; DISKETTE_STATUS DB ? ; SINGLE BYTE OF RETURN CODE INFO FOR STATUS TIME_OUT EQU 80H ; ATTACHMENT FAILED TO RESPOND BAD_SEEK EQU 40H ; SEEK OPERATION FAILED BAD_NEC EQU 20H ; NEC CONTROLLER HAS FAILED BAD_CRC EQU 10H ; BAD CRC ON DISKETTE READ DMA_BOUNDARY EQU 09H ; ATTEMPT TO DMA ACROSS 64K BOUNDARY BAD_DMA EQU 08H ; DMA OVERRUN ON OPERATION RECORD_NOT_FND EQU 04H ; REQUESTED SECTOR NOT FOUND WRITE_PROTECT EQU 03H ; WRITE ATTEMPTED ON WRITE PROT DISK BAD_ADDR_MARK EQU 02H ; ADDRESS MARK NOT FOUND BAD_CMD EQU 01H ; BAD COMMAND PASSED TO DISKETTE I/O ; NEC_STATUS DB 7 DUP(?) ; STATUS BYTES FROM NEC ;-------------------------------- ; VIDEO DISPLAY DATA AREA ;-------------------------------- CRT_MODE DB ? ; CURRENT CRT MODE CRT_COLS DW ? ; NUMBER OF COLUMNS ON SCREEN CRT_LEN DW ? ; LENGTH OF REGEN IN BYTES CRT_START DW ? ; STARTING ADDRESS IN REGEN BUFFER CURSOR_POSN DW 8 DUP(?) ; CURSOR FOR EACH OF UP TO 8 PAGES CURSOR_MODE DW ? ; CURRENT CURSOR MODE SETTING ACTIVE_PAGE DB ? ; CURRENT PAGE BEING DISPLAYED ADDR_6845 DW ? ; BASE ADDRESS FOR ACTIVE DISPLAY CARD CRT_MODE_SET DB ? ; CURRENT SETTING OF THE 3X8 REGISTER CRT_PALLETTE DB ? ; CURRENT PALLETTE SETTING COLOR CARD PAGE ;-------------------------------- ; CASSETTE DATA AREA ;-------------------------------- EDGE_CNT DW ? ; TIME COUNT AT DATA EDGE CRC_REG DW ? ; CRC REGISTER LAST_VAL DB ? ; LAST INPUT VALUE ;-------------------------------- ; TIMER DATA AREA ;-------------------------------- TIMER_LOW DW ? ; LOW WORD OF TIMER COUNT TIMER_HIGH DW ? ; HIGH WORD OF TIMER COUNT TIMER_OFL DB ? ; TIMER HAS ROLLED OVER SINCE LAST READ ;COUNTS_SEC EQU 18 ;COUNTS_MIN EQU 1092 ;COUNTS_HOUR EQU 65543 ;COUNTS_DAY EQU 1573040 = 1800B0H ;------------------------------- ; SYSTEM DATA AREA ;------------------------------- BIOS_BREAK DB ? ; BIT 7 = 1 IF BREAK KEY HAS BEEN DEPRESSED RESET_FLAG DW ? ; WORD = 1234H IF KEYBOARD RESET UNDERWAY DATA ENDS ; ;-------------------------------- ; EXTRA DATA AREA ;-------------------------------- XXDATA SEGMENT AT 50H STATUS_BYTE DB ? XXDATA ENDS ; ;-------------------------------- ; VIDEO DISPLAY BUFFER ;-------------------------------- VIDEO_RAM SEGMENT AT 0B800H REGEN LABEL BYTE REGENW LABEL WORD DB 16384 DUP(?) VIDEO_RAM ENDS ; ;-------------------------------- ; ROM RESIDENT CODE ;-------------------------------- ROMCODE SEGMENT AT 0F000H DB 57344 DUP(?) ; FILL LOWEST 56K DB '5700051 CORP. IBM 1981' ; COPYRIGHT NOTICE ROMCODE ENDS ; ;-------------------------------- ; PROGRAM SEGMENT PREFIX ;-------------------------------- ; PROGRAM SEGMENT INT20 DW ;INT 20 for DOS return MEMORYSIZE DW ;TOTAL MEMORY SIZE CALLDOS_FAR DB 5 DUP(?) ; LONG CALL DOS DISPATCHER TERMADDR DB 4 DUP(?) ; TERMINATE ADDRESS (ip,cs) CTRLBREAK DB 4 DUP(?) ; ctrl_break EXIT ADDRESS RESERVED DB 4ah DUP(?) ; RESERVED AREA FCB_ONE DB 10H DUP(?) ; unopened fcb #1 FCB_TWO DB 10H DUP(?) ; unopened fcb #2 PARM_LENGTH DB ; LENGTH OF PARAMETERS PARM_FIELD DB 19 DUP(?) ; PARAMETER STRING DATA ; SUBTTL PAGE ORG 100H ; DEFAULT ENTRY ADDRESS PROGRAM_ENTRY EQU $ ning with hex-F are ignored ; PUSH ES