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FPGA: add BS-X "hole" (regs 09-0b)

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This commit is contained in:
Maximilian Rehkopf 2012-11-07 22:31:28 +01:00
parent 648569d900
commit 1f5af01bc0
2 changed files with 11 additions and 0 deletions
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9
verilog/sd2snes/address.v
View File

@ -33,6 +33,7 @@ module address(
output msu_enable,
output srtc_enable,
output use_bsx,
output bsx_tristate,
input [14:0] bsx_regs,
output dspx_enable,
output dspx_dp_enable,
@ -115,6 +116,14 @@ wire BSX_IS_CARTROM = ((bsx_regs[7] & (SNES_ADDR[23:22] == 2'b00))
|(bsx_regs[8] & (SNES_ADDR[23:22] == 2'b10)))
& SNES_ADDR[15];
wire BSX_HOLE_LOHI = (bsx_regs[9] & ~SNES_ADDR[23]) | (bsx_regs[10] & SNES_ADDR[23]);
wire BSX_IS_HOLE = BSX_HOLE_LOHI
& (bsx_regs[2] ? (SNES_ADDR[21:20] == {bsx_regs[11], 1'b0})
: (SNES_ADDR[22:21] == {bsx_regs[11], 1'b0}));
assign bsx_tristate = (MAPPER == 3'b011) & ~BSX_IS_CARTROM & ~BSX_IS_PSRAM & BSX_IS_HOLE;
assign IS_WRITABLE = IS_SAVERAM
|((MAPPER == 3'b011)
? BSX_IS_PSRAM

2
verilog/sd2snes/main.v
View File

@ -440,6 +440,7 @@ address snes_addr(
.bs_page_offset(bs_page_offset),
.bs_page(bs_page),
.bs_page_enable(bs_page_enable),
.bsx_tristate(bsx_tristate),
//SRTC
.srtc_enable(srtc_enable),
//uPD77C25
@ -739,6 +740,7 @@ assign SNES_DATABUS_OE = (dspx_enable | dspx_dp_enable) ? 1'b0 :
((IS_ROM & SNES_CS)
|(!IS_ROM & !IS_SAVERAM & !IS_WRITABLE & !IS_FLASHWR)
|(SNES_READr[0] & SNES_WRITEr[0])
| bsx_tristate
);
assign SNES_DATABUS_DIR = (!SNES_READr[0] | (!SNES_PARD & (r213f_enable | snescmd_rd_enable)))