SMW Magic Project MSU1 (v2) MAP16 source

lorom

 ;Map16 Copy
 ORG $0FF9D0 ;14336 bytes = $3800 bytes
 ;Map16 Low Byte Table = $7E:C800
 ;Map16 High Byte Table = $7F:C800
 !RAMHigh = $7FC00B ;$7F9C7B
 !RAMLow = $7FC00C ;$7F9C7C

 LoadMap16LowTable:
	PHP
	PHA
	PHX
	PHY
	REP #$10 ; 16 bit X Y
	SEP #$20 ; 8 bit A
	STZ $2000 ;Set S-MSU1 Address for Data Port
	STZ $2001
	STZ $2002
	STZ $2003

  -	LDA $2000 ;Don't start the port to RAM until it's ready
	AND #$80
	CMP #$80
	BNE -

	STZ !RAMLow ;RAM : Low Byte, Bytes Recieved.
	STZ !RAMHigh ;RAM : High Byte, Bytes Recieved.
	LDX #$00
	TXS

LoadLowLoop:
  -	LDA $2001 ;Byte Port from S-MSU1
	STA [$7EC800],X ;To Map16 Low Byte Table
	LDA !RAMLow ;Check if $FF bytes has been received.
	CMP #$FF
	BEQ HighByteUp ;If yes, go to "HighByteUp"
	INC !RAMLow ;If no, add 1 to received bytes (low)
	INX ;Add 1 to X
	BRA - ;Loop

HighByteUp:
	INC !RAMLow
	INC !RAMHigh
	INX
	LDA !RAMHigh
	CPX #$3800
	BEQ LoadMap16HighTable
	JMP LoadLowLoop

LoadMap16HighTable:
	STZ $2000
	LDA #$38
	STA $2001
	STZ $2002
	STZ $2003

  -	LDA $2000
	AND #$80
	CMP #$80
	BNE -

	STZ !RAMLow ;RAM : Low Byte, Bytes Recieved.
	STZ !RAMHigh ;RAM : High Byte, Bytes Recieved.
	LDX #$00


LoadHighLoop:
  -	LDA $2001
	STA [$7FC800],X
	LDA !RAMLow
	CMP #$FF
	BEQ HighByteUpHigh
	INC !RAMLow
	INX
	BRA -

HighByteUpHigh:
	INC !RAMLow
	INC !RAMHigh
	INX
	LDA !RAMHigh
	CMP #$38
	BEQ Stop
	JMP LoadHighLoop

Stop:
	PLP ;Gets everything back to normal
	PLA
	PLX
	PLY

Stop2:
	LDA.b #$10  ;Insert replaced opcodes here
	STA.w $1DF5
	RTL


ORG $009AC0 ;Insert JSL somewhere after the Level Loading Routine.
	JSL $0FF9D0
	NOP