X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=hexed%2Ftransfer.S;h=ef5bf5d9cdea359f717110f513f7ebc406d53b9f;hb=HEAD;hp=e4d5a2b61b4c3c4771e794e37081d5a482585295;hpb=f28eaaadd73dce455231733228d3f0cbbf4462de;p=megadrive.git

diff --git a/hexed/transfer.S b/hexed/transfer.S
index e4d5a2b..ef5bf5d 100644
--- a/hexed/transfer.S
+++ b/hexed/transfer.S
@@ -88,9 +88,22 @@
 .endm
 
 recv_byte:
+	moveq.l		#0,d0
 	recv_one_byte 1
 	rts
 
+# receive 1 16bit word to d0
+#  in: a1 - data port
+#  trash: d1,d2
+recv_word:
+	recv_one_byte
+	move.b		d0,d2
+	recv_one_byte
+	lsl.w		#8,d2
+	move.b		d0,d2
+	move.w		d2,d0
+	rts
+
 # receive address/size to d0 (3 bytes BE)
 #  in: a1 - data port
 #  trash: d1,d2
@@ -107,6 +120,58 @@ recv_ad:
 	move.l		d2,d0
 	rts
 
+# send 1 byte in d0
+#  in: a1 - data port
+#  trash: d1,d2
+send_byte:
+	send_one_byte
+	rts
+
+.macro switch_to_output
+0: /*Lwait_tl_low: PC should switch to rx mode before lowering tl */
+	move.b		(a1),d0
+	btst.b		#4,d0
+	bne		0b /*Lwait_tl_low*/
+
+	move.b		#0x4f,(0xa1000b).l
+	move.b		#0x40,(a1)
+.endm
+
+.equ sat_maxsize, (80*8+0x200) /* sprites+max_align */
+
+# make sure cache is invalidated
+# note: VRAM copy doesn't seem to help here
+# note2: cache is updated as data is written
+#  in: d0 - vdp reg5, a0 = 0xc00000
+#  trash: d1,d2,a2
+invalidate_sprite_cache:
+	move.w		#0x8f02,4(a0)		/* auto increment 2 */
+	lsl.b		#1,d0			/* upper byte of sat address */
+	move.b		d0,d1
+	lsr.b		#6,d1			/* 15:14 dst addr */
+	and.b		#0x3f,d0		/* assemble cmd */
+	lsl.w		#8,d0
+	swap		d0
+	move.b		d1,d0
+	move.l		d0,4(a0)
+
+	move.l		#0xffe000,a2
+	move.l		#sat_maxsize/2-1,d2
+0:
+	move.w		(a0),(a2)+
+	dbra		d2,0b
+
+	bset		#30,d0			/* VRAM write */
+	move.l		d0,4(a0)
+
+	move.l		#0xffe000,a2
+	move.l		#sat_maxsize/2-1,d2
+0:
+	move.w		(a2)+,(a0)
+	dbra		d2,0b
+	rts
+
+
 
 do_transfer:
 	lea		0xa10005,a1
@@ -118,14 +183,27 @@ do_transfer:
 	bne		return
 
 	bsr		recv_byte
-	cmp.b		#CMD_MD_SEND,d0		/* sent to us */
-	beq		transfer_recv
-	cmp.b		#CMD_MD_RECV,d0		/* recv from us */
-	beq		transfer_send
-	bra		return
+	cmp.b		#CMD_FIRST,d0
+	bcs		return
+	cmp.b		#CMD_LAST+1,d0
+	bcc		return
+	sub.b		#CMD_FIRST,d0
 
+	lsl.w		#2,d0
+	lea		(jumptab,pc,d0),a0
+	jmp		(a0)
+jumptab:
+	bra		pcc_transfer_recv	/* sent to us */
+	bra		pcc_transfer_send	/* recv from us */
+	bra		pcc_jump
+	bra		pcc_io
+	bra		pcc_loadstate
+	bra		pcc_vram_send
+	bra		pcc_test_code
 
-transfer_recv:
+
+/* receive data from PC */
+pcc_transfer_recv:
 	bsr		recv_ad
 	move.l		d0,a0
 	bsr		recv_ad
@@ -135,31 +213,225 @@ tr_recv_loop:
 	recv_one_byte
 	move.b		d0,(a0)+
 	subq.l		#1,d3
-	bne		tr_recv_loop
+	bgt		tr_recv_loop
 	bra		return
 
-transfer_send:
+
+/* send data to PC */
+pcc_transfer_send:
 	bsr		recv_ad
 	move.l		d0,a0
 	bsr		recv_ad
 	move.l		d0,d3
 
-0: /*Lwait_tl_low:*/
-	move.b		(a1),d0
-	btst.b		#4,d0
-	bne		0b /*Lwait_tl_low*/
-
-	move.b		#0x4f,(0xa1000b).l
-	move.b		#0x40,(a1)
+	switch_to_output
 
 tr_send_loop:
 	move.b		(a0)+,d0
 	send_one_byte
 	subq.l		#1,d3
-	bne		tr_send_loop
+	bgt		tr_send_loop
+	bra		return
+
+
+/* call specified location */
+pcc_jump:
+	bsr		recv_ad
+	move.l		d0,a0
+	jsr		(a0)
+	bra		return
+
+
+/* do simple i/o commands */
+pcc_io:
+	moveq.l		#0,d4
+	bsr		recv_byte
+	move.b		d0,d4
+	bsr		recv_byte
+	lsl.l		#8,d4
+	move.b		d0,d4
+
+pcc_io_loop:
+	move.b		#0x40,(0xa1000b).l	/* input mode */
+
+	sub.w		#1,d4
+	bmi		return
+
+	bsr		recv_byte
+	move.b		d0,d3			/* cmd */
+
+	bsr		recv_ad
+	move.l		d0,a2			/* addr */
+
+	cmp.b		#IOSEQ_W32, d3
+	beq		pcc_io_w32
+	cmp.b		#IOSEQ_W16, d3
+	beq		pcc_io_w16
+	cmp.b		#IOSEQ_W8, d3
+	bne		pcc_io_rx
+
+pcc_io_w8:
+	bsr		recv_byte
+	move.b		d0,(a2)
+	bra		pcc_io_loop
+
+pcc_io_w16:
+	bsr		recv_byte
+	move.b		d0,d3
+	bsr		recv_byte
+	lsl.w		#8,d3
+	move.b		d0,d3
+	move.w		d3,(a2)
+	bra		pcc_io_loop
+
+pcc_io_w32:
+	bsr		recv_byte
+	move.b		d0,d3
+	bsr		recv_byte
+	lsl.w		#8,d3
+	move.b		d0,d3
+	bsr		recv_byte
+	lsl.l		#8,d3
+	move.b		d0,d3
+	bsr		recv_byte
+	lsl.l		#8,d3
+	move.b		d0,d3
+	move.l		d3,(a2)
+	bra		pcc_io_loop
+
+pcc_io_rx:
+	switch_to_output
+
+	cmp.b		#IOSEQ_R32, d3
+	beq		pcc_io_r32
+	cmp.b		#IOSEQ_R16, d3
+	beq		pcc_io_r16
+	cmp.b		#IOSEQ_R8, d3
+	bne		return
+
+pcc_io_r8:
+	move.b		(a2),d0
+	bsr		send_byte
+	bra		pcc_io_loop
+
+pcc_io_r16:
+	move.w		(a2),d3
+	move.w		d3,d0
+	lsr.w		#8,d0
+	bsr		send_byte
+	move.b		d3,d0
+	bsr		send_byte
+	bra		pcc_io_loop
+
+pcc_io_r32:
+	move.l		(a2),d3
+	move.l		d3,d0
+	swap		d0
+	lsr.l		#8,d0
+	bsr		send_byte
+	move.l		d3,d0
+	swap		d0
+	bsr		send_byte
+	move.w		d3,d0
+	lsr.w		#8,d0
+	bsr		send_byte
+	move.b		d3,d0
+	bsr		send_byte
+	bra		pcc_io_loop
+
+
+/* PicoDrive savestate load */
+pcc_loadstate:
+	/* write VRAM */
+	move.l		#0xc00000,a0
+	move.w		#0x8f02,4(a0)		/* auto increment 2 */
+
+	move.l		#0x40000000,4(a0)
+	move.l		#0x10000/2-1,d3
+tr_do_vram_loop:
+	bsr		recv_word
+	move.w		d0,(a0)
+	dbra		d3, tr_do_vram_loop
+
+	/* write cram */
+	move.l		#0xc0000000,4(a0)
+	move.l		#0x80/2-1,d3
+tr_do_cram_loop:
+	bsr		recv_word
+	move.w		d0,(a0)
+	dbra		d3, tr_do_cram_loop
+
+	/* write vsram */
+	move.l		#0x40000010,4(a0)
+	move.l		#0x80/2-1,d3
+tr_do_vsram_loop:
+	bsr		recv_word
+	move.w		d0,(a0)
+	dbra		d3, tr_do_vsram_loop
+
+	/* recv and write regs */
+	lea		0xffe000,a3
+	move.l		a3,a2
+	moveq.l		#0x20-1,d3
+tr_do_vdpreg_recv_loop:
+	bsr		recv_byte
+	move.b		d0,(a2)+
+	dbra		d3, tr_do_vdpreg_recv_loop
+
+	move.l		a3,a2
+	moveq.l		#0,d3
+tr_do_vdpreg_loop:
+	move.b		d3,d1
+	or.b		#0x80,d1
+	lsl.w		#8,d1
+	move.b		(d3,a2),d1
+	move.w		d1,4(a0)
+	addq.l		#1,d3
+	cmp.b		#0x17,d3	/* FIXME: r23 might cause DMA or.. */
+	bne		0f		/* ..something and hang VDP.. */
+	add.b		#1,d3		/* ..so we skip it */
+0:
+	cmp.b		#0x20,d3
+	blt		tr_do_vdpreg_loop
+
+	moveq.l		#0,d0
+	move.b		5(a3),d0
+	bsr		invalidate_sprite_cache
+
+
+0:	bra		0b
+
 	bra		return
 
 
+pcc_vram_send:
+	/* write VRAM */
+	move.l		#0xc00000,a0
+	move.w		#0x8f02,4(a0)		/* auto increment 2 */
+	move.l		#0,4(a0)		/* VRAM read, addr 0 */
+	move.l		#0x10000/2-1,d4
+
+	switch_to_output
+
+tr_vram_send_loop:
+	move.w		(a0),d3
+	move.w		d3,d0
+	lsr.w		#8,d0
+	bsr		send_byte
+	move.b		d3,d0
+	bsr		send_byte
+	dbra		d4,tr_vram_send_loop
+
+	bra		return
+
+
+
+/* some random code */
+pcc_test_code:
+	bra		return
+
+
+
 return:
 	move.b		#0,(0xa1000b).l	/* all inputs */
 	move.l		#0xffe000,a1
@@ -168,7 +440,8 @@ return:
 	move.l		d2,(a1)+
 	move.l		d3,(a1)+
 	move.l		a0,(a1)+
-	bra		return_to_main
+	rts
+#	bra		return_to_main
 
 
 # vim:filetype=asmM68k