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Merge pull request #1773 from smunaut/fix_spram_model 

ice40: Fix SPRAM model to keep data stable if chipselect is low
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David Shah 2020-03-15 17:16:57 +00:00 committed by GitHub
parent acb341745d acd9eeef7c
commit 685392fed8
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1 changed files with 8 additions and 5 deletions
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13
techlibs/ice40/cells_sim.v
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@ -2350,16 +2350,19 @@ module SB_SPRAM256KA (
if (off) begin
DATAOUT <= 0;
end else
if (CHIPSELECT && !STANDBY && !WREN) begin
DATAOUT <= mem[ADDRESS];
end else begin
if (CHIPSELECT && !STANDBY && WREN) begin
if (STANDBY) begin
DATAOUT <= 'bx;
end else
if (CHIPSELECT) begin
if (!WREN) begin
DATAOUT <= mem[ADDRESS];
end else begin
if (MASKWREN[0]) mem[ADDRESS][ 3: 0] = DATAIN[ 3: 0];
if (MASKWREN[1]) mem[ADDRESS][ 7: 4] = DATAIN[ 7: 4];
if (MASKWREN[2]) mem[ADDRESS][11: 8] = DATAIN[11: 8];
if (MASKWREN[3]) mem[ADDRESS][15:12] = DATAIN[15:12];
DATAOUT <= 'bx;
end
DATAOUT <= 'bx;
end
end
`endif