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GR8RAM
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Remove CKE

This commit is contained in:
Zane Kaminski 2021-04-18 03:59:56 -04:00
parent 4fd3d2ff3f
commit 8e35f6fc16
1 changed files with 17 additions and 36 deletions
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53
cpld/GR8RAM.v
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@ -325,7 +325,7 @@ module GR8RAM(C25M, PHI0, nRES, nRESout, SetFW,
end end
/* SDRAM address/command */ /* SDRAM address/command */
output reg RCKE = 1; output RCKE = 1;
output reg nRCS = 1; output reg nRCS = 1;
output reg nRAS = 1; output reg nRAS = 1;
output reg nCAS = 1; output reg nCAS = 1;
@ -333,117 +333,98 @@ module GR8RAM(C25M, PHI0, nRES, nRESout, SetFW,
wire RefReqd = LS[1:0] == 2'b11; wire RefReqd = LS[1:0] == 2'b11;
always @(posedge C25M) begin always @(posedge C25M) begin
case (PS[3:0]) case (PS[3:0])
0: begin // NOP CKE / CKD 0: begin // NOP
RCKE <= PSStart;
nRCS <= 1'b1; nRCS <= 1'b1;
nRAS <= 1'b1; nRAS <= 1'b1;
nCAS <= 1'b1; nCAS <= 1'b1;
nSWE <= 1'b1; nSWE <= 1'b1;
SDOE <= 0; SDOE <= 0;
end 1: begin // ACT CKE / NOP CKD end 1: begin // ACT / NOP (ACT)
RCKE <= IS==6 || (((ROMSpecSELr && nWEr) || RAMSpecSELr) && IS==7);
nRCS <= ~(IS==6 || (((ROMSpecSELr && nWEr) || RAMSpecSELr) && IS==7)); nRCS <= ~(IS==6 || (((ROMSpecSELr && nWEr) || RAMSpecSELr) && IS==7));
nRAS <= 1'b0; nRAS <= 1'b0;
nCAS <= 1'b1; nCAS <= 1'b1;
nSWE <= 1'b1; nSWE <= 1'b1;
SDOE <= 0; SDOE <= 0;
end 2: begin // RD CKE / NOP CKD end 2: begin // RD / NOP (RD)
RCKE <= (ROMSpecSELr || RAMSpecSELr) && nWEr && IS==7;
nRCS <= ~((ROMSpecSELr || RAMSpecSELr) && nWEr && IS==7); nRCS <= ~((ROMSpecSELr || RAMSpecSELr) && nWEr && IS==7);
nRAS <= 1'b1; nRAS <= 1'b1;
nCAS <= 1'b0; nCAS <= 1'b0;
nSWE <= 1'b1; nSWE <= 1'b1;
SDOE <= 0; SDOE <= 0;
end 3: begin // NOP CKE / CKD end 3: begin // NOP
RCKE <= (ROMSpecSELr || RAMSpecSELr) && nWEr && IS==7;
nRCS <= 1'b1; nRCS <= 1'b1;
nRAS <= 1'b1; nRAS <= 1'b1;
nCAS <= 1'b1; nCAS <= 1'b1;
nSWE <= 1'b1; nSWE <= 1'b1;
SDOE <= 0; SDOE <= 0;
end 4: begin // NOP CKD end 4: begin // NOP
RCKE <= 1'b0;
nRCS <= 1'b1; nRCS <= 1'b1;
nRAS <= 1'b1; nRAS <= 1'b1;
nCAS <= 1'b1; nCAS <= 1'b1;
nSWE <= 1'b1; nSWE <= 1'b1;
SDOE <= 0; SDOE <= 0;
end 5: begin // NOP CKD end 5: begin // NOP
RCKE <= 1'b0;
nRCS <= 1'b1; nRCS <= 1'b1;
nRAS <= 1'b1; nRAS <= 1'b1;
nCAS <= 1'b1; nCAS <= 1'b1;
nSWE <= 1'b1; nSWE <= 1'b1;
SDOE <= 0; SDOE <= 0;
end 6: begin // NOP CKD end 6: begin // NOP
RCKE <= 1'b0;
nRCS <= 1'b1; nRCS <= 1'b1;
nRAS <= 1'b1; nRAS <= 1'b1;
nCAS <= 1'b1; nCAS <= 1'b1;
nSWE <= 1'b1; nSWE <= 1'b1;
SDOE <= 0; SDOE <= 0;
end 7: begin // NOP CKE / CKD end 7: begin // NOP
RCKE <= IS==6 || (RAMWR && IS==7);
nRCS <= 1'b1; nRCS <= 1'b1;
nRAS <= 1'b1; nRAS <= 1'b1;
nCAS <= 1'b1; nCAS <= 1'b1;
nSWE <= 1'b1; nSWE <= 1'b1;
SDOE <= 0; SDOE <= 0;
end 8: begin // WR AP / NOP CKE (WR AP) end 8: begin // WR AP / NOP (WR AP)
// NOP CKD / WR AP
RCKE <= IS==6 || (RAMWR && IS==7);
nRCS <= ~(IS==6 || (RAMWR && IS==7)); nRCS <= ~(IS==6 || (RAMWR && IS==7));
nRAS <= 1'b1; nRAS <= 1'b1;
nCAS <= 1'b0; nCAS <= 1'b0;
nSWE <= 1'b0; nSWE <= 1'b0;
SDOE <= IS==6 || (RAMWR && IS==7); SDOE <= IS==6 || (RAMWR && IS==7);
end 9: begin // NOP CKE / NOP CKD end 9: begin // NOP
RCKE <= (IS==6) || ((ROMSpecSELr || RAMSpecSELr) && IS==7) ||
(RefReqd && (IS==4 || IS==5 || IS==6 || IS==7));
nRCS <= 1'b1; nRCS <= 1'b1;
nRAS <= 1'b1; nRAS <= 1'b1;
nCAS <= 1'b1; nCAS <= 1'b1;
nSWE <= 1'b1; nSWE <= 1'b1;
SDOE <= 0; SDOE <= 0;
end 10: begin // PC all / NOP CKD (PC all) end 10: begin // PC all / NOP (PC all)
RCKE <= (IS==6) || ((ROMSpecSELr || RAMSpecSELr) && IS==7) ||
(RefReqd && (IS==4 || IS==5 || IS==6 || IS==7));
nRCS <= ~((IS==6) || ((ROMSpecSELr || RAMSpecSELr) && IS==7) || nRCS <= ~((IS==6) || ((ROMSpecSELr || RAMSpecSELr) && IS==7) ||
(RefReqd && (IS==4 || IS==5 || IS==6 || IS==7))); (RefReqd && (IS==4 || IS==5 || IS==6 || IS==7)));
nRAS <= 1'b0; nRAS <= 1'b0;
nCAS <= 1'b1; nCAS <= 1'b1;
nSWE <= 1'b0; nSWE <= 1'b0;
SDOE <= 0; SDOE <= 0;
end 11: begin // AREF / NOP CKD (AREF) end 11: begin // AREF
RCKE <= RefReqd && (IS==4 || IS==5 || IS==6 || IS==7);
nRCS <= ~(RefReqd && (IS==4 || IS==5 || IS==6 || IS==7)); nRCS <= ~(RefReqd && (IS==4 || IS==5 || IS==6 || IS==7));
nRAS <= 1'b0; nRAS <= 1'b0;
nCAS <= 1'b0; nCAS <= 1'b0;
nSWE <= 1'b1; nSWE <= 1'b1;
SDOE <= 0; SDOE <= 0;
end 12: begin // NOP CKD end 12: begin // NOP
RCKE <= 1'b0;
nRCS <= 1'b1; nRCS <= 1'b1;
nRAS <= 1'b1; nRAS <= 1'b1;
nCAS <= 1'b1; nCAS <= 1'b1;
nSWE <= 1'b1; nSWE <= 1'b1;
SDOE <= 0; SDOE <= 0;
end 13: begin // NOP CKD end 13: begin // NOP
RCKE <= 1'b0;
nRCS <= 1'b1; nRCS <= 1'b1;
nRAS <= 1'b1; nRAS <= 1'b1;
nCAS <= 1'b1; nCAS <= 1'b1;
nSWE <= 1'b1; nSWE <= 1'b1;
SDOE <= 0; SDOE <= 0;
end 14: begin // NOP CKD end 14: begin // NOP
RCKE <= 1'b0;
nRCS <= 1'b1; nRCS <= 1'b1;
nRAS <= 1'b1; nRAS <= 1'b1;
nCAS <= 1'b1; nCAS <= 1'b1;
nSWE <= 1'b1; nSWE <= 1'b1;
SDOE <= 0; SDOE <= 0;
end 15: begin // NOP CKD end 15: begin // NOP
RCKE <= 1'b0;
nRCS <= 1'b1; nRCS <= 1'b1;
nRAS <= 1'b1; nRAS <= 1'b1;
nCAS <= 1'b1; nCAS <= 1'b1;