6809 Assembly programming for the Vectrex

The FM-7 is one of a series of Fujitsu computers released in Japan

With a pair of 6809 CPU's it was widely popular in Japan, and is one of the few 6809 computers released.

In these tutorials we'll learn the about the FM7, and write some simple programs for it

	Vectrex
Cpu	Main: 1.5mhz 6809
Ram	1k Ram
Rom	32k
Sound	AY-3-8912
Max Resolution	INFINITE!!!

Vectrex!

Useful Links!
PlayVectrex - Vectrex Programming Manuals

Memory Map

Address	Purpose
$0000	Cartridge Rom
$8000	Unused
$C800	Bios RAM
$C880	User RAM
$CC00	unused
$D000	PIA
$D010	PIA Mirror
$E000	Minestorm ROM
$F000	Bios ROM

OS Calls

Group	Address	Name	AltName	DP (Entry/Exit)	Details	Example
Init	$F18B	INITALL	INTALL	$D0	Full Vectrex initialization
Init	$F164	INITMSC	INTMSC	$C8	Initialize misc. parameters
Init	$F14C	INITPIA	INTPIA	$D0	Initialize PIA
Init	$F272	INITPSG	INTPSG	$D0	Initialize the �REQx� area (sound mirror).
Init	$F533	IREQ	INTREQ	-	Initialize the 'REQZ' area
Init	$F000	POWER	PWRUP	-	Power-up handler
Drawing	$F2E6	DEFLOK	---C1:C1048576B1:B1048576	$D0	Overcome scan collapse circuitry
Drawing	$F192	FRAM20	FRWAIT	$D0	Wait for frame boundary (Pause for next frame)
Drawing	$F29D	INT1Q	-	$D0	Set beam intensity 1/4 ($1F)
Drawing	$F2A5	INT3Q	-	$D0	Set beam intensity 3/4 ($5F)
Drawing	$F2AB	INTENS	-	$D0	Set beam intensity A (0-127)
Drawing	$F2A9	INTMAX	-	$D0	Set beam intensity 4/4 (7F)
Drawing	$F2A1	INTMID	INT2Q	$D0	Set beam intensity 2/4 ($3F)
Drawing	$F30C	POSIT1	-	$D0	Position relative vector List X (1x scale)	db Y,X
Drawing	$F308	POSIT2	-	$D0	Position relative vector (2x scale)
Drawing	$F30E	POSITB	-	$D0	Position relative vector list X Scale B
Drawing	$F2FC	POSITD	-	$D0	Position relative vector (X,Y)=(B,A) scale 1x
Drawing	$F312	POSITN	-	$D0	Position relative vector (X,Y)=(B,A) scale T1LOLC
Drawing	$F310	POSITX	-	$D0	Release integrators and position beam, lfrom X	db Y,X
Drawing	$F2F2	POSWID	-	$D0	Release integrators and position beam using 16-bit (Y,X) values from address X	dw Y,X
Drawing	$F34F	CZERO	ZEGO	$D0	Depending ZSKIP, zero integrators and set the sample / hold for active ground.
Drawing	$F35B	ZEREF	ZEREF	$D0	Set active ground sample / hold to zero volts.
Drawing	$F34A	ZERO.DP	ZERO.DP	$D0	DP=$D0... Zero integrators and set active ground
Drawing	$F36B	ZERO.	ZERO	$D0	Zero the integrators only
Drawing	$F354	ZEROIT	ZEROIT	$D0	Zero integrators and set active ground
Diffy	$F610	DANROT	DROT	-	Rotate �Diffy� style list A=Angle B=no of Vectors X=Source list U=Dest
Diffy	$F433	DASHE	DSHDF1	$D0	Draw dashed lines from 'DIFFY' list
Diffy	$F434	DASHEL	DSHDF	$D0	Draw dashed lines from 'DIFFY' list A=Vectors-1 X=List
Diffy	$F437	DASHY	DASHDF	$D0	Draw dashed lines from 'DIFFY' list X
Diffy	$F3DF	DIFFAB	-	$D0	Draw from 'DIFFY' style list (B,A)=(X,Y)
Diffy	$F3CE	DIFFAX	-	$D0	Draw from 'DIFFY' style list X=List
Diffy	$F3D8	DIFFX	TDIFFY	$D0	Draw from 'DIFFY' style list A=Vectors-1 B=Scale X=List
Diffy	$F3DD	DIFFY	-	$D0	Draw from 'DIFFY' style list X=List
Diffy	$F3D6	DIFLST	-	$D0	Draw from 'DIFFY' style list
Diffy	$F616	DIFROT	ADROT	-	Rotate �DIFFY� style list X=Source U=Dest ANGLE
Diffy	$F3D2	DIFTIM	-	$D0	Draw from 'DIFFY' style list B=scale X=List
Diffy	$F3DA	DIFTLS	LDIFFY	$D0	Draw from 'DIFFY' style list A=Vectors-1, X=List
Diffy	$F613	DISROT	BDROT	-	'DIFFY' style rotate B=vector count X=source list U=Dest
Duffy	$F3BE	DUFFAB	-	$D0	Move a single vector from the current beam position using the relative vector values given in �D� (X,Y)=(B,A)
Duffy	$F3AD	DUFFAX	-	$D0	Draw from 'DUFFY' style list X=list
Duffy	$F3BC	DUFFY	-	$D0	Draw from 'DUFFY' style list X=list
Duffy	$F3BC	DUFLTLS	TDUFFY	$D0	Draw from 'DUFFY' style list B=length X=List
Duffy	$F3B5	DUFLST	-	$D0	Draw from 'DUFFY' style list X=list
Duffy	$F3B1	DUFTIM	-	$D0	Draw from 'DUFFY' style list B=length X=List
Diffy	$F3B9	DUFLST		$D0	A=Vectors-1 X=List
Dot	$F2D5	DIFDOT	-	$D0	Draw dots according to 'DIFFY' format X=List pointer
Dot	$F2C5	DOT	-	$D0	Turn on beam for dot
Dot	$F2C3	DOTAB	-	$D0	Draw Dot at relative (X,Y) pos (B,A)
Dot	$F2DE	DOTPAK	DOTPCK	$D0	Draw dots according to 'PACKET' format X=list
Dot	$F2BE	DOTTIM	-	$D0	Draw one dot from 'DIFFY' style list B=on time X=List
Dot	$F2C1	DOTX	-	$D0	Draw one dot from 'DIFFY' style list X
Packet	$F46E	DASHY3	DASHPK	$D0	Draw dashed lines from 'PACKET' list X
Packet	$F408	PAC1X	PACK1X	$D0	Draw according to �Packet� style list X scale 1x
Packet	$F404	PAC2X	PACK2X	$D0	Draw according to �Packet� style list X scale 2x
Packet	$F40E	PACB	TPACK	$D0	Draw from 'PACKET' list X B=Scale
Packet	$F410	PACKET	-	$D0	Draw according to �Packet� style list X
Packet	$F40C	PACXX	LPACK	$D0	Draw from 'PACKET' style list X=list
Packet	$F61F	POTATA	PROT	-	'PACKET' style rotate A=Angle X=Source List U=Dest List
Packet	$F622	POTATE	APROT	-	'PACKET' style rotate
Raster	$F37A	POSDRAS	MSSPOS	$D0	Print $80 terminated String U at (X,Y) relative pos (B,A)
Raster	$F378	POSNRAS	RSTPOS	$D0	Display raster message from U
Raster	$F498	RASTER	MRASTR	$D0	Display raster string from MESSAGE
Raster	$F495	RASTUR	RASTER	$D0	Display raster string from U
Raster	$F87C	SADD	SCRADD	-	Add contents of score D to BCD at address X
Raster	$F880	SADD2	STKADD	-	Add stack to indicated score
Raster	$F85E	SHADD	BYTADD	-	Add contents of 'A' to indicated score	A = 2-digit BCD number X = Score field pointer
Raster	$F391	SHIPSAT	SHIPX	$D0	Display markers (count remaining)
Raster	$F393	SHIPSHO	DSHIP	$C8	Display markers (count remaining) A=ascii B=remaining X=Pos
Raster	$F373	SIZPRAS	RSTSIZ	$D0	Display raster message from U
Raster	$F38C	TEXPOS	TXTPOS	$D0	Draw Strings from U (0 terminated)	dc.b Y,X,"TXT",$80 dc.b Y,X,"TXT",$80 dc.b 0
Raster	$F385	TEXSIZ	TXTSIZ	$D0	Display raster message from U
Controller	$F1B4	ENPUT	DBNCE	$D0	Read controller switches and debounce switch status. (A=Response mask)
Controller	$F8D8	HIGHSCR	HISCR	-	Calculate high score and save for logo C=Score Field U=Highscore
Controller	$F1BA	INPUT	-	$D0	Read controller buttons
Controller	$F7A9	OPTION	SELOPT	-	Fetch number of players and options from player A + B = No of players (0-9)
Controller	$F1F8	PANG	JOYBIT	$D0	Read joystick UDLR
Controller	$F1F5	PBANG4	JOYSTK	$D0	Read the absolute position of the controller joysticks.
Controller	$F84F	SCLR	-	-	Clear indicated score X
Controller	$F8C7	WINNER	-	-	Determine highest score X or U
Rotate	$F610	DANROT	DROT	-	'DIFFY' style rotate
Rotate	$F616	DIFROT	ADROT	-	'DIFFY' style rotate
Rotate	$F613	DISROT	BDROT	-	'DIFFY' style rotate
Rotate	$F61F	POTATA	PROT	-	'PACKET' style rotate
Rotate	$F622	POTATE	APROT	-	'PACKET' style rotate X=Soource U=Dest (ANGLE)
Rotate	$F5FF	RATOT	LROT90	$C8	Rotate a single line A=Initial Y B=Angle
Rotate	$F603	ROTAR	ALNROT	$C8	Rotate a single line A=Initial Y (ANGLE)
Rotate	$F601	ROTOR	LNROT	$C8	Rotate a single line A=Initial Y B=Angle
Maths	$F584	ABSVAL	ABSAB	-	Form absolute value for 'A' & 'B' registers
Maths	$F58B	AOK	ABSB	-	Form absolute value for 'B' register
Maths	$F57E	BITE	DECBIT	-	Decode bit position A=Bit number (0-7)
Maths	$F593	COMPAS	CMPASS	$C8	Return angle for given delta 'Y:X'
Maths	$F5D9	COSGET	COSINE	-	Calculate the cosine of 'A'
Maths	$F511	RAND3	-	-	Calculate new random number from SEED
Maths	$F517	RANDOM	-	-	Calculate new random number from SEED
Maths	$F663	RCOS	LCSINE	$C8	Multiply 'LEG' by previous cosine value
Maths	$F661	RCOSA	MCSINE	$C8	Multiply 'A' by previous cosine value
Maths	$F65D	RSIN	LSINE	$C8	Multiply 'LEG' by previous sine value
Maths	$F65B	RSINA	MSINE	$C8	Multiply 'A' by previous sine value WSINE
Maths	$F5EF	SINCOS	-	$C8	Calculate the sine and cosine of 'ANGLE'
Maths	$F5DB	SINGET	SINE	$C8	Calculate the sine of 'A'
Misc	$F67F	BAGAUX	BLKMV1	-	Transfer A+1 bytes (127 max) from source U destination X
Misc	$F545	CLR256		-	Clear 256 bytes at address X
Misc	$F542	CLRMEM	CLREX	-	Clear executive area of memory ($C800 - $C8FF)
Misc	$F53F	CLRSON	BCLR	-	Clear 'B' bytes from X
Misc	$F55E	DEKR	DECTMR	-	Decrement interval timers (XTMR0 � XTMR5)
Misc	$F55A	DEKR3	D3TMR	-	Decrement 3 interval timers (XTMR0 � XTMR2)
Misc	$F57A	DEL	-	-	Delay execution for a minimum of 20 cycles (B=Delay)
Misc	$F57D	DEL13	-	-	Delay execution for 13 cycles
Misc	$F579	DEL20	-	-	Delay execution for 20 cycles
Misc	$F575	DEL28	-	-	Delay execution for 28 cycles
Misc	$F571	DEL33	-	-	Delay execution for 33 cycles
Misc	$F56D	DEL38	-	-	Delay execution for 38 cycles
Misc	$F1AA	DPIO	-	-	Set 6809 �DP� register for I/O accesses ($D0)
Misc	$F1AF	DPRAM	-	-	Set 6809 �DP� register for RAM accesses ($C8)
Misc	$F552	FILL	BLKFIL	-	Set a block of memory A=data B=bytes X=dest
Misc	$F8FF	FINDBOX	BXTEST	-	Symmetric collison test	A = Box �Y� dimension (delta �Y�) B = Box �X� dimension (delta �X�) X = Y:X coordinates of point to be tested Y = Y:X coordinates of box center
Misc	$F548	GILL	CLRBLK	-	Clear D bytes of memory from X
Misc	$F550	NEGSOM	CLR80	-	Set B bytes at memory X to $80
Misc	$F8E5	OFF1BOX	OFF1BX	-	Off-center symmetric collision test
Misc	$F8F3	OFF2BOX	OFF2BX	-	Off-center symmetric collision text
Misc	$F683	STFAUX	BLKMOV	-	Transfer �A� bytes (0-127) from source �U� to destination �X�
Sound	$F92E	AXE	EXPLOD	$C8	Complex explosion sound effect U=table
Sound	$F9CA	LOUDIN	SETAMP	$C8	Set amplitude in �REQx� B=Volume
Sound	$F259	PSG	WRPSG	$D0	Write to PSG A=PSG Addr B=PSG data X=mirror
Sound	$F284	PSGLPU	PSGMIR	$D0	Send sound string to PSG from U and mirror X
Sound	$F27D	PSGLUP	PSGLST	$D0	Send sound string to PSG from U
Sound	$F256	PSGX	WRREG	$D0	Write to PSG and Morror A=Psg Addr B=PSG Data
Sound	$F687	REPLAY	-	$C8	Set tune Sequence to list U
Sound	$F289	REQOUT	-	$D0	Send 'REQX' to PSG and mirror
Sound	$F690	SOPLAY	ASPLAY	$C8	Set tune sequence with alternate note set X=user not table U=Tune List
Sound	$F68D	SPLAY	-	$C8	Set tune Sequence to list U
Sound	$F742	XPLAY	-	$C8	Terminate current tune
Sound	$F692	YOPLAY	TPLAY	$C8	Set tune Sequence to list U

OS Vars

Address	Name	Details	Notes
$C800	REG0	Channel A: Fine tone period
$C801	REG1	Channel A: Course tone period
$C802	REG2	Channel B: Fine tone period
$C803	REG3	Channel B: Course tone period
$C804	REG4	Channel C: Fine tone period
$C805	REG5	Channel C: Course tone period
$C806	REG6	Noise period
$C807	REG7	Tone / Noise enables
$C808	REG8	Channel A: Amplitude
$C809	REG9	Channel B: Amplitude
$C80A	REGA	Channel C: Amplitude
$C80B	REGB	Fine envelope period
$C80C	REGC	Course envelope period
$C80D	REGD	Envelope shape / cycle
$C80E	REGE	I/O port data register
$C80F	TRIGGR	Collective Switch Settings
$C811	EDGE (HEDGES)	Used by button handlers
$C812	KEY0	Controller #1 - Switch #0 (Leftmost)
$C813	KEY1	Controller #1 - Switch #1
$C814	KEY2	Controller #1 - Switch #2
$C815	KEY3	Controller #1 - Switch #3 (Rightmost)
$C816	KEY4	Controller #2 - Switch #0 (Leftmost)
$C817	KEY5	Controller #2 - Switch #1
$C818	KEY6	Controller #2 - Switch #2
$C819	KEY7	Controller #2 - Switch #3 (Rightmost)
$C81A	POTRES	Joystick resolution limit
$C81B	POT0	Joystick #1 - 'X' Axis
$C81C	POT1	Joystick #1 - 'Y' Axis
$C81D	POT2	Joystick #2 - 'X' Axis
$C81E	POT3	Joystick #2 - 'Y' Axis
$C81F	EPOT0 (DPOT0)	Controller #1: Right / left joystick pot enable (must be $00 or $01)
$C820	EPOT1 (DPOT1	Controller #1: Up / down joystick pot enable (must be $00 or $03)
$C821	EPOT2 (DPOT2)	Controller #2: Right / left joystick #2 enable (must be $00 or $05)
$C822	EPOT3 (DPOT3)	Controller #2: Up / down joystick #2 enable (must be $00 or $07)
$C823	LIST	Number Of Vectors to be drawn
$C824	ZSKIP	Flag controlling whether integrators will be zeroed:	Z=no NZ=Yes
$C825 - $C826	FRAME	Frame Counter
$C827	TENSTY	Contains the last value used for the intensity setting
$C828	DWELL	Dot �ON� time
$C829	DASH	Dash pattern for drawing routines
$C82A - $C82B	SIZRAS	Raster Message Size ($HHWW)	$F848=lrg $FC38 = sml
$C82C - $C82D	MESAGE	Used by string display functions to hold pointer to message to be displayed.
$C82E	XTMR0 (X0)	?
$C82F	XTMR1 (X1)	Countdown timer
$C830	XTMR2 (X2)	Countdown timer
$C831	XTMR3 (X3)	Countdown timer
$C832	XTMR4 (X4)	Countdown timer
$C833	XTMR5 (X5)	Countdown timer
$C834	ABSY	Working storage for �CMPASS�
$C835	ABSX	Working storage for �CMPASS�
$C836	ANGLE	Angle for rotation
$C837 - $C838	WSINE (SINE)	Location for parameter passing. Generally contains the last sine value calculated
$C839 � C83A	WCSINE (COSINE)	Location for parameter passing. Generally contains the last cosine value calculated.
$C83B	LEG	Executive Working Storage
$C83C	LAG	Used by transformation functions
$C83D - $C83E	FRMTIM (XMSEC)	Frame rate
$C83F	REQ0	Envelope shape / cycle
$C840	REQ1	Course envelope period
$C841	REQ2	Fine envelope period
$C842	REQ3	Channel C: Amplitude
$C843	REQ4	Channel B: Amplitude
$C844	REQ5	Channel A: Amplitude
$C845	REQ6	Tone / noise enables
$C846	REQ7	Noise period
$C847	REQ8	Channel C: Course tone period
$C848	REQ9	Channel C: Fine tone period
$C849	REQA	Channel B: Course tone period
$C84A	REQB	Channel B: Fine tone period
$C84B	REQC	Channel A: Course tone period
$C84C	REQD	Channel A: Fine tone period
$C84D - $C84E	DOREMI	Note table pointer
$C84F - $C850	FADE	Working storage for �SELOPT� and tune player subroutines
$C851	VIBE	Working storage for tune player subroutines
$C853 - $C854	TUNE	?
$C855	NEWGEN	Working storage for tune player subroutines
$C856	TSTAT	Working storage for tune player subroutines
$C857	RESTC	Working storage for tune player subroutines
$C858	RATEA	Working storage for �EXPLOD�
$C859	VIBA	Working storage for �EXPLOD�
$C85A	RATEB	Working storage for �EXPLOD�
$C85B	VIBB	Working storage for �EXPLOD�
$C85C	RATEC	Working storage for �EXPLOD�
$C85D	VIBC	Working storage for �EXPLOD�
$C85E	FADEA	Working storage for �SELOPT� and tune player subroutines
$C85F	FADEB	Working storage for �SELOPT� and tune player subroutines
$C860	FADEC	Working storage for �SELOPT� and tune player subroutines
$C861 - $C862	TONEA	Working storage for �SELOPT� and tune player subroutines
$C863 - $C864	TONEB	Working storage for �SELOPT� and tune player subroutines
$C865 - $C866	TONEC	Working storage for tune player subroutines
$C86A	GAP	Allocated but not used by Mine Storm or Executive
$C86F - $C870	F1FREQ	Allocated but not used by Mine Store or Executive
$C80F - $C810	TRIGGR	Current controller button status.
$C867	SATUS	Working storage for �EXPLOD�
$C868	LATUS	Allocated but not used by Mine Storm or Executive
$C869	XATUS	Allocated but not used by Mine Storm or Executive
$C86B - $C86C	B1FREQ	Allocated but not used by Mine Storm or Executive
$C86D - $C86E	B2FREQ	Allocated but not used by Mine Store or Executive
$C871	FEAST	Allocated but not used by Mine Storm or Executive
$C872	PEDGE	Allocated but not used by Mine Storm or Executive
$C873	NEDGE	Allocated but not used by Mine Storm or Executive
$C874 � $C875	K1FREQ	Allocated but not used by Mine Storm or Executive
$C876	BACON	Allocated but not used by Mine Storm or Executive
$C877	XACON	Working storage for �EXPLOD�
$C878	SPEKT	Allocated but not used by Mine Store or Executive
$C879	PLAYRS (PLAYRZ)	Number of players ($01 - $09)
$C87A	OPTION (GAMZ)	Number of player options ($01 - $09)
$C87B - $C87C	SEED	Seed used by the random number generator
$C87D � C87F	RANCID	Working storage for random number generators
$C880	SBTN	First memory location available for use by a game
$C881	SJOY	Joystick mask (used by MineStorm)
$C883	ETMP1	Mine Storm: Temporary working storage
$C884	ETMP2	Mine Storm: Temporary working storage
$C885	ETMP3	Mine Storm: Temporary working storage
$C886	ETMP4	Mine Storm: Temporary working storage
$C887	ETMP5	Mine Storm: Temporary working storage
$C888	ETMP6	Mine Storm: Temporary working storage
$C889	ETMP7	Mine Storm: Temporary working storage
$C88A	ETMP8	Mine Storm: Temporary working storage
$C88B	ETMP9	Mine Storm: Temporary working storage
$C88C	ETMP10	Mine Storm: Temporary working storage
$C88F	TEMP1	Mine Storm: Temporary working storage
$C890	TEMP2	Mine Storm: Temporary working storage
$C891	TEMP3	Mine Storm: Temporary working storage
$C892	TEMP4	Mine Storm: Temporary working storage
$C893	TEMP5	Mine Storm: Temporary working storage
$C894	TEMP6	Mine Storm: Temporary working storage
$C895	TEMP7	Mine Storm: Temporary working storage
$C896	TEMP8	Mine Storm: Temporary working storage
$C897	TEMP9	Mine Storm: Temporary working storage
$C898 - $C89A	TEMP10	Mine Storm: Temporary working storage
$C89B	ACTPLY	Mine Storm: Currently active player ($00 or $02)
$C89C - $C89E	TMR1	Mine Storm: Timer
$C89F - $C8A1	TMR2	Mine Storm: Timer
$C8A2 - $C8A4	TMR3	Mine Storm: Timer
$C8A5 - $C8A7	TMR4	Mine Storm: Timer
$C8A8 - $C8AE	SCOR1	Holds player 1�s score... 6 digits $80 terminated ascii
$C8AF � C8B5	SCOR2	Holds player 2�s score
$C8EB - $C8F1	HISCOR (HEIGH)	Contains ASCII high score

Hardware Registers

$D000	8-bit port �B� (Control bits) [CNTRL]
$D001	8-bit port �A� (DAC and PSC data) [DAC]
$D002	Port �B� direction control [DCNTRL]
$D003	Port �A� direction control [DDAC]
$D004-7	Timer #1 [T1LOLC, T1HOC, T1LOL, T1HOL]
$D008-9	Timer #2 [T2LOLC, T2HOC]
$D00A	Shift register [SHIFT]
$D00B	Auxiliary control register [ACNTRL]
$D00C	Peripheral control register [PCNTRL]
$D00D	Interrupt flag register [IFLAG]
$D00E	Interrupt enable register [IENABL]
$D00F	ORA

The holy trinity - Diffy, Duffy and Packet
The Vectrex has three vector graphics formats!

Diffy lists are a list of connected lines
Duffy lists are an undrawn 'start position' followed by a list of connected lines.
Packet lists are lists of lines ($FF) and undrawn movements of the pen ($00)

Below is the same graphic drawn in all 3 formats:

Diffy	Duffy	Packet
dc.b 7 ;ItemCount -1 ;dc.b $00,$00 ;No initial move on Diffy dc.b $F6,$F5 ;0 Y,X Draw this dc.b $E6,$0C ;1 Y,X Draw this dc.b $FA,$F6 ;2 Y,X Draw this dc.b $F9,$0A ;3 Y,X Draw this dc.b $06,$08 ;4 Y,X Draw this dc.b $08,$F6 ;5 Y,X Draw this dc.b $17,$0E ;6 Y,X Draw this dc.b $0E,$F2 ;7 Y,X Draw this	dc.b 8 ;ItemCount -1 dc.b $00,$00 ;0 Y,X Move to this point dc.b $F6,$F5 ;1 Y,X Draw this dc.b $E6,$0C ;2 Y,X Draw this dc.b $FA,$F6 ;3 Y,X Draw this dc.b $F9,$0A ;4 Y,X Draw this dc.b $06,$08 ;5 Y,X Draw this dc.b $08,$F6 ;6 Y,X Draw this dc.b $17,$0E ;7 Y,X Draw this dc.b $0E,$F2 ;8 Y,X Draw this	dc.b $00,$00,$00 ;0 Y,X Move to this point dc.b $FF,$F6,$F5 ;1 Y,X Draw this dc.b $FF,$E6,$0C ;2 Y,X Draw this dc.b $FF,$FA,$F6 ;3 Y,X Draw this dc.b $FF,$F9,$0A ;4 Y,X Draw this dc.b $FF,$06,$08 ;5 Y,X Draw this dc.b $FF,$08,$F6 ;6 Y,X Draw this dc.b $FF,$17,$0E ;7 Y,X Draw this dc.b $FF,$0E,$F2 ;8 Y,X Draw this dc.B $01 ;End of list

Character Map

The Vectrex has some character printing routines - they have a built in character map, which has upper case and a few system characters.

Direct Page

The Vectrex uses two Direct page settings

$C8 points to RAM
$D0 points to Hardware registers

With ASW (Our assembler) use ASSUME dpr:$xx to tell the assembler where the direct page is... this is called SETDP on some assemblers.

AY Registers

The procedure for setting and reading AY registers is not quite direct... the method is shown here

Select Register:
RegNum -> $D001
#$19 -> $D000
#$01 -> $D000

Write Selected Register:
New Value -> $D001
#$11 -> $D000
#$01 -> $D000

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