; Assume mem 8-Bit, Index 16-Bit
; SRCOFFSET 	= data to store offset
; DEST		= where in Vram to store it
; SIZE		= size of the data
; REGSMODE	= register & transfer mode.($1801->port $2118, mode 1)
; CHANNELDATA	= dma channel init byte. EX:
;		  ($0210) $00 = $4310, $02 = init to $420b
;
;########################################################
; Macro to store data into Vram using a DMA transfer	#
;########################################################
DMA .macro (SRCOFFSET,DEST,SIZE,REGSMODE,CHANNELDATA)
 PHB
 PHA
 PHP

 REP #$10
 sep #$20

 ldy #!$0000
 lda #$00
 xba
 lda CHANNELDATA	; load the channel to use. $10 from above
 tay
 stz $420B		; clear dma init port

 LDA SRCOFFSET+2	; load the bank to transfer from
 sta $4304,y

 REP #$30
 lda REGSMODE
 sta $4300,y

 Lda SRCOFFSET		; load 16-Bit offset
 sta $4302,y

 LDa SIZE		; size of data to transfer
 sta $4305,y

 LDa DEST		; vram location
 sta $2116
 
 sep #$20
 lda CHANNELDATA+1	; start the transfer
 sta $420b

 PLP
 PLA
 PLB
.endm