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GR8RAM
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Put FullIOEN back

This commit is contained in:
Zane Kaminski 2020-02-26 03:37:20 -05:00
parent ef9b5852fb
commit ac8cf35610
1 changed files with 8 additions and 3 deletions
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11
cpld/GR8RAM.v
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@ -27,9 +27,11 @@ module GR8RAM(C7M, C7M_2, Q3, PHI0in, PHI1in, nRES, nMode,
input nWE; // 6502 R/W
output [10:0] RA; // DRAM/ROM address
assign RA[10:8] = CASel ? Addr[21:19] : Addr[10:8];
assign RA[7:0] = ~nIOSTRB ? Bank+1 :
(~CASel & nIOSEL & nIOSTRB) ? Addr[18:11] :
(CASel & nIOSEL & nIOSTRB) ? Addr[7:0] : 8'h00;
assign RA[7:0] =
(~nIOSTRB & ~FullIOEN) ? {7'b0000001, Bank[0]} :
(~nIOSTRB & FullIOEN) ? Bank+1 :
( nIOSTRB & ~CASel & nIOSEL) ? Addr[18:11] :
( nIOSTRB & CASel & nIOSEL) ? Addr[7:0] : 8'h00;
/* Select Signals */
wire BankSELA = A[3:0]==4'hF;
@ -38,6 +40,7 @@ module GR8RAM(C7M, C7M_2, Q3, PHI0in, PHI1in, nRES, nMode,
wire AddrMSELA = A[3:0]==4'h1;
wire AddrLSELA = A[3:0]==4'h0;
LCELL BankWR_MC (.in(BankSELA & ~nWE & ~nDEVSEL & REGEN), .out(BankWR)); wire BankWR;
LCELL SetWR_MC (.in(SetSELA & ~nWE & ~nDEVSEL & REGEN), .out(SetWR)); wire SetWR;
LCELL RAMSEL_MC (.in(RAMSELA & ~nDEVSEL & REGEN), .out(RAMSEL)); wire RAMSEL;
LCELL AddrHWR_MC (.in(AddrHSELA & ~nWE & ~nDEVSEL & REGEN), .out(AddrHWR)); wire AddrHWR;
LCELL AddrMWR_MC (.in(AddrMSELA & ~nWE & ~nDEVSEL & REGEN), .out(AddrMWR)); wire AddrMWR;
@ -67,6 +70,7 @@ module GR8RAM(C7M, C7M_2, Q3, PHI0in, PHI1in, nRES, nMode,
/* 6502-accessible Registers */
reg REGEN = 0; // Register enable
reg IOROMEN = 0; // IOSTRB ROM enable
reg FullIOEN = 0; // Set to enable full I/O ROM space
reg [7:0] Bank = 0; // Bank register for ROM access
reg [23:0] Addr = 0; // RAM address register
@ -183,6 +187,7 @@ module GR8RAM(C7M, C7M_2, Q3, PHI0in, PHI1in, nRES, nMode,
// Set register in middle of S6 if accessed.
if (S==6) begin
if (BankWR) Bank[7:0] <= D[7:0]; // Bank
if (SetWR) FullIOEN <= D[7:0] == 8'hE5;
IncAddrL <= RAMSEL;
IncAddrM <= AddrLWR & Addr[7] & ~D[7];