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C02/include/c64.a02
Curtis F Kaylor 70f03c4db5 Added standard library files include/*
2018-01-28 13:30:49 -05:00

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; c02 Program Initialization Code for Unexpanded VIC-20
;System Specific ASCII Key Mappings
DELKEY EQU $7F ;Delete/Backspace Key (Delete)
ESCKEY EQU $03 ;Escape/Stop Key (RUN/STOP)
RTNKEY EQU $0D ;Return/Enter Key (RETURN)
;Zero Page Locations
; EQU $00 ;USR JMP
adray1 EQU $03 ;Vector: Convert Floating Point to Signed Integer
adray2 EQU $05 ;Vector: Convert Integet to Floating Point
charac EQU $07 ;Search Character for Scanning BASIC Text Input
endchr EQU $08 ;Search Character for Statement Terminator or Quote
trmpos EQU $09 ;Column Position of Cursor before Last SPC or TAB
verckb EQU $0A ;Flag: Load or Verify (BASIC)
count EQU $0B ;Index into Text Input Buffer/Number of Array Subscripts
dimflg EQU $0C ;Flags for Routines that Locate or Build an Array
valtyp EQU $0D ;Type of Data (String or Numeric)
intflg EQU $0E ;Type of Numeric Data (Integer or Floating Point)
garbfl EQU $0F ;Flag for LIST, Garbage Collection, and Program Terminators
subflg EQU $10 ;Subscript Reference to Array or User Defined Function Call
inpflg EQU $11 ;Is Data Input to GET, READ, or INPUT?
tansgn EQU $12 ;Sign of Result of TAN or SIN Function
channl EQU $13 ;Current I/O Channel (CMD Logical File) Number
linnum EQU $14 ;Integer Line Number Value
temppt EQU $16 ;Pointer to Next Availabale Space in Temporary String Stack
lastpt EQU $17 ;Pointer to Address of Last String in Temporary String Stack
tempst EQU $19 ;Descriptor Stack for Temporary Strings
index EQU $22 ;Miscellaneous Temporary Pointers and Save Area
; $24
resho EQU $26 ;Floating Point Multiplication Work Area
txttab EQU $2B ;Pointer to Start of BASIC Program Text
vartab EQU $2D ;Pointer to Start of BASIC Variable Storage Area
arytab EQU $2F ;Pointer to Start of BASIC Array Storage Area
strend EQU $31 ;Pointer to Start of Free RAM
fretop EQU $33 ;Pointer to Bottom of String Text Storage Area
frespc EQU $35 ;Temporary Pointer for Strings
memsiz EQU $37 ;Pointer to Highest Address Used by BASIC
curlin EQU $39 ;Current BASIC Line Number
oldlin EQU $3B ;Previous BASIC Line Number
oldtxt EQU $3D ;Pointer to Address of Current BASIC Statement
datlin EQU $3F ;Current DATA Line Number
datptr EQU $41 ;Pointer to Address of Current DATA Item
inpptr EQU $43 ;Pointer to Source of GET, READ, or INPUT Information
varnam EQU $45 ;Current Variable Name
varpnt EQU $47 ;Pointer to Current BASIC Variable Value
forpnt EQU $49 ;Temporary Pointer to Index Variable Used by FOR
opptr EQU $4B ;Math Operator Table Displacement
opmask EQU $4D ;Mask for Comparison Operator
defpnt EQU $4E ;Pointer to Current FN Descriptor
dscpnt EQU $50 ;Temporary Pointer to Current String Descriptor
; $52 ;current string length
four6 EQU $53 ;Constant for Garbage Collection
jmper EQU $54 ;Jump to Function Instruction
; $57 ;BASIC Numeric Work Area
fac1 EQU $61 ;Floating Point Accumulator #1
facexp EQU $61 ;Floating Point Accumulator #1: Exponent
facho EQU $62 ;Floating Point Accumulator #1: Mantissa
facsgn EQU $66 ;Floating Point Accumulator #1: Sign
sgnflg EQU $67 ;Number of Terms in Series Evaluation
bits EQU $68 ;Floating Point Accumulator #1: Overflow Digit
fac2 EQU $69 ;Floating Point Accumulator #2
argexp EQU $69 ;Floating Point Accumulator #2: Exponent
argho EQU $6E ;Floating Point Accumulator #2: Mantissa
argsgn EQU $6F ;Floating Point Accumulator #2: Sign
facov EQU $70 ;Low Order Mantissa Byte of Floating Point Accumulator #1
fbufpt EQU $71 ;Series Evaluation Pointer
chrget EQU $73 ;Subroutine: Get Next BASIC Text Character
chrgot EQU $79 ;Entry Point: Get Current BASIC Text Character
txtptr EQU $7A ;Pointer to Current BASIC Text Character
pointb EQU $7C ;Entry Point: Test Character in Accumulator
exit EQU $8A ;RTS at end of CHRGET, CHRGOT, and POINTB Routines
rndx EQU $8B ;RND Function Seed Value
status EQU $90 ;Kernal I/O Status Word
stkey EQU $91 ;Flag: Was STOP Key Pressed
svxt EQU $92 ;Timing Constant for Tape Reads
verck EQU $93 ;Flag: Load or Verify (Kernal)
c3po EQU $94 ;Flag: Serial Bus - Output Character was Buffered
bsour EQU $95 ;Buffered Character for Serial Bus
syno EQU $96 ;Cassette Block Synchronization Number
xsav EQU $97 ;Temporary .X Register Save Area
ldtnd EQU $98 ;Number of Open I/O Files, Index to End of File Tables
dfltn EQU $99 ;Default Input Device (Set to 0 for Keyboard)
dflto EQU $9A ;Default Output (CMD) Device (Set to 3 for Screen)
prty EQU $9B ;Tape Character Parity
dpsw EQU $9C ;Flag: Tape Byte Received
msflg EQU $9D ;Flag: Kernal Message Control
ptr1 EQU $9E ;Tape Pass 1 Error Log Index
ptr2 EQU $9F ;Tape Pass 2 Error Log Correction Index
time EQU $A0 ;Software Jiffy Clock
; EQU $A3 ;Temporary Data Storage Area
cntdn EQU $A5 ;Cassette Synchronization Character Countdown
bufpnt EQU $A6 ;Count of Characters in Tape I/O Buffer
inbit EQU $A7 ;RS-232 Input Bits/Tape I/O Miscellaneous Flag
bitci EQU $A8 ;RS-232 Input Bit Count/Tape Error Flag
rinone EQU $A9 ;RS-232 Flag: Check for Start Bit/Tape Character Type Flag
ridata EQU $AA ;RS-232 Input Byte Buffer
riprty EQU $AB ;RS-232 Input Parity/Cassette Leader Counter
sal EQU $AC ;Pointer to Starting Address of Load/Screen Scrolling
eal EQU $AE ;Pointer to Ending Address of Load (End of Program)
cmp0 EQU $B0 ;Used to Determine Value of SVXT
; EQU $B1 ;Used in Timing of Tape Reads
tape1 EQU $B2 ;Pointer: Start of Tape Buffer
bitts EQU $B4 ;RS-232 Output Bit Count/Tape Load Receive Flag
nxtbit EQU $B5 ;RS-232 Next Bit to Send/Tape EOT Flag
rodata EQU $B6 ;RS-232 Output Byte Buffer
fnlen EQU $B7 ;Length of Current Filename
la EQU $B8 ;Current Logical File Number
sa EQU $B9 ;Current Secondary Address
fa EQU $BA ;Current Device Number
fnadr EQU $BB ;Pointer: Current Filename
roprt EQU $BD ;RS-232 Output Parity/Tape Character Being Read or Sent
fsblk EQU $BE ;Cassette Read/Write Block Count
mych EQU $BF ;Tape Input Byte Buffer
cas1 EQU $C0 ;Tape Motor Interlock
stal EQU $C1 ;I/O Start Address
memuss EQU $C3 ;Tape Load Temporary Address
lste EQU $C5 ;Matrix Coordinate of Last Key Pressed
ndx EQU $C6 ;Number of Characters in Keyboard Buffer
rvs EQU $C7 ;Flag: Print Reverse Characters
indx EQU $C8 ;Pointer: End of Logical Line for Input
lxsp EQU $C9 ;Cursor X.Y Position at Start of Input
sfdx EQU $CB ;Matrix Coordinate of Current Key Pressed
blnsw EQU $CC ;Cursor Blink Enable
blnct EQU $CD ;Timer Countdown to Blink Cursor
gdbln EQU $CE ;Character Under Cursor
blnon EQU $CF ;Flag: Was Last Cursor Blink On or Off
crsw EQU $D0 ;Flag: Input from Keyboard or Screen
pnt EQU $D1 ;Pointer to Address of Current Screen Line
pntr EQU $D3 ;Cursor Column on Current Line
qtsw EQU $D4 ;Flag: Editor in Quote Mode?
lnmx EQU $D5 ;Maximum Length of Physical Screen Line
tblx EQU $D6 ;Current Cursor Physical Line Number
; EQU $D7 ;Temporary Storage for ASCII Value of Last Character Printed
insrt EQU $D8 ;Insert Mode (Number of Inserts)
ldtb1 EQU $D9 ;Screen Line Link Table
user EQU $F3 ;Pointer to Address of Current Screen Color RAM Location
keytab EQU $F5 ;Vector: Keyboard Decode Table
ribuf EQU $F7 ;Pointer: RS-232 Input Buffer
robuf EQU $F8 ;Pointer: RS-232 Output Buffer
frekzp EQU $FB ;Four Free Bytes of Zero Page for User Programs
baszpt EQU $FF ;BASIC Temporary Data for Floating Point to ASCII Conversion
;Page 1 Locations
bad EQU $0100 ;Tape Input Error Log
; EQU $013F ;Microprocessor Stack
;Basic and Kernal Working Storage
buf EQU $0200 ;BASIC Line Editor Input Buffer
lat EQU $0259 ;Kernal Table of Active Logical File Numbers
fat EQU $0263 ;Kernal Table of Device Numbers for Each Logical File
sat EQU $026D ;Kernal Table of Secondary Addressed for Each Logical File
keyd EQU $0277 ;Keyboard Buffer (Queue)
memstr EQU $0281 ;Pointer: Operating System Start of Memory
memsiz EQU $0283 ;Pointer: Operating System End of Memory
timout EQU $0285 ;Flag: Kernal Variable for IEEE Timeout
color EQU $0286 ;Current Foreground Color Text
gdcol EQU $0287 ;Color of Character Under Cursor
hibase EQU $0288 ;Top Page of Screen Memory
xmax EQU $0289 ;Maximum Keyboard Buffer Size
rptflg EQU $028A ;Flag: Which Key Will Repeat?
kount EQU $028B ;Counter for Timing Delay Between Key Repeats
delay EQU $028C ;Counter for Timing Delay Until First Key Repeat Begins
shflag EQU $028D ;Flag: SHIFT/CTRL/Logo Keypress
lstshf EQU $028E ;Last Pattern SHIFT/CTRL/Logo Keypress
keylog EQU $028F ;Vector to Keyboard Table Setup Routine
mode EQU $0291 ;Flag: Change Character Sets with SHIFT/Logo Keypress
autodn EQU $0292 ;Flag: Screen Scroll Enabled
m51ctr EQU $0293 ;RS-232: Mock 6551 Control Register
m51cdr EQU $0294 ;RS-232: Mock 6551 Command Register
m51adj EQU $0295 ;RS-232: Non-Standard Bit Timing (Not Implemented)
rsstat EQU $0297 ;RS-232: Mock 6551 Status Register
bitnum EQU $0298 ;RS-232: Number of Bits Left to be Sent/Received
baudof EQU $0299 ;RS-232: Time Required to Send a Bit
ridbe EQU $029B ;RS-232: Index to End of Receive Buffer
ridbs EQU $029C ;RS-232: Index to Start of Receive Buffer
rodbs EQU $029D ;RS-232: Index to Start of Transmit Buffer
rodbe EQU $029E ;RS-232: Index to End of Transmit Buffer
irqtmp EQU $029F ;Save Area for IRQ Vector During Cassette I/O
enabl EQU $02A1 ;RS-232 Interrupts Enabled
; EQU $02A2 ;CIA #1 Control Register B Activity During Cassette I/O
; EQU $02A3 ;Save Area for CIA #1 Interrupt Control Register
; EQU $02A4 ;Save Area for CIA #1 Control Register A
; EQU $02A5 ;Temporary Index to Next Line for Screen Scrolling
; EQU $02A6 ;PAL/NTSC Flag
; EQU $02A7 ;Unused
; EQU $02C0 ;Sprite 11
;BASIC Indirect Vector Table
ierror EQU $0300 ;Vector to Print BASIC Error Message Routine
imain EQU $0302 ;Vector to Main BASIC Program Loop
icrnch EQU $0304 ;Vector to Crunch ASCII Keyword into Tokens
iqplop EQU $0306 ;Vector to List BASIC Token as ASCII Text
igone EQU $0308 ;Vector to Execute Next BASIC Token
ieval EQU $030A ;Vector to Evaluate Single-Term Arithmetic Expression
;Register Storage Area
sareg EQU $030C ;Storage Area for .A Register (Accumulator)
sxreg EQU $030D ;Storage Area for .X Index Register
syreg EQU $030E ;Storage Area for .Y Index Register
spreg EQU $030F ;Storage Area for .P (Status) Register
;Miscellaneous Vectors
usrpok EQU $0310 ;JMP Instruction for User Function
usradd EQU $0311 ;Address of USR Routine
; EQU $0313 ;Unused
cinv EQU $0314 ;Vector to IRQ Interrupt Routine
cbinv EQU $0316 ;Vector: BRK Instruction Interrupt
nminv EQU $0318 ;Vector: Non-Maskabke Interrupt
;Kernal Indirect Vectors
iopen EQU $031A ;Vector to Kernal OPEN Routine
iclose EQU $031C ;Vector to Kernal CLOSE Routine
ichkin EQU $031E ;Vector to Kernal CHKIN Routine
ickout EQU $0320 ;Vector to Kernal CKOUT Routine
iclrch EQU $0322 ;Vector to Kernal CLRCHN Routine
ibasin EQU $0324 ;Vector to Kernal CHRIN Routine
ibsout EQU $0326 ;Vector to Kernal CHROUT Routine
istop EQU $0328 ;Vector to Kernal STOP Routine
igetin EQU $032A ;Vector to Kernal GETIN Routine
iclall EQU $032C ;Vector to Kernal CLALL Routine
usrcmd EQU $032E ;Vector to User Defined Command (Unused)
iload EQU $0330 ;Vector to Kernal LOAD Routine
isave EQU $0332 ;Vector to Kernal SAVE Routine
; $0334 ;Unused
tbuffer EQU $033C ;Cassette I/O Buffer
; $03FC ;Unused
vicscn EQU $0400 ;Video Screen Memory Area
; $07F8 ;Sprite Shape Data Pointers
; $0800 ;BASIC Program Text
; $8000 ;Autostart ROM Cartridge
vicclr EQU $D800 ;Color RAM
;Kernal Routines
chrin EQU $FFCF ;Input Character to Channel
chrout EQU $FFD2 ;Output Character to Channel
getin EQU $FFE4 ;Read Character from Keyboard Buffer
;Machine Language Basic Stub
ORG $1001 ;Start Directly Above Stack
basic: DC $0C, $10 ; Pointer to Next Line (4109)
DC $00, $00 ; Line Number (0)
DC $9E ; SYS
DC $20 ; ' '
DC $34, $31, $31 ,$30 ; "4110"
DC $00 ;End of Line Marker
DC $00, $00 ;End of Basic Program
JMP main ;Execute Program
;Poll Keyboard for Character
plkey EQU getin ;Read Character from Keyboard Buffer
;Read Character from Console
;Wait for Character from Console
getkey: JSR plkey ;Poll Keyboard
BEQ getkey ;If No Key, Loop
RTS
;Delete Previous Character
delchr: RTS
;Advance Character to Next line
newlin: LDA #$0D ;Load C/R into Accumulator
;Print Character to Console
prchr EQU chrout ;
;Print Byte as Two-Digit Hex Number to Console
prbyte: PHA ;Save Accumulater
LSR ;Shift Hi Nybble to Low Nybble
LSR
LSR
LSR
JSR prhex ; and Print it
PLA ;Restore Accumulator
; and fall into prhex
;Print Low Nybble as Hex Digit to Console
prhex: AND #$0F ;Strip High Nybble
CMP #$0A ;If Low Nybble >= 10
BCC prhexc ;
ADC #$06 ; Convert ':' to 'A'...
prhexc: ADC #$30 ;Convert to ASCII Character
JMP prchr ;Print Hex Digit and Return
exit: RTS ;Return to Monitor
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