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`ifdef cyclonev
`define SYNCPATH 262
`define SYNCSETUP 522
`define COMBPATH 0
`endif
`ifdef cyclone10gx
`define SYNCPATH 219
`define SYNCSETUP 268
`define COMBPATH 0
`endif
// fallback for when a family isn't detected (e.g. when techmapping for equivalence)
`ifndef SYNCPATH
`define SYNCPATH 0
`define SYNCSETUP 0
`define COMBPATH 0
`endif
// This is a purely-synchronous flop, that ABC9 can use for sequential synthesis.
(* abc9_flop, lib_whitebox *)
module $__MISTRAL_FF_SYNCONLY (
input DATAIN, CLK, ENA, SCLR, SLOAD, SDATA,
output reg Q
);
specify
if (ENA) (posedge CLK => (Q : DATAIN)) = `SYNCPATH;
if (ENA) (posedge CLK => (Q : SCLR)) = `SYNCPATH;
if (ENA) (posedge CLK => (Q : SLOAD)) = `SYNCPATH;
if (ENA) (posedge CLK => (Q : SDATA)) = `SYNCPATH;
$setup(DATAIN, posedge CLK, `SYNCSETUP);
$setup(ENA, posedge CLK, `SYNCSETUP);
$setup(SCLR, posedge CLK, `SYNCSETUP);
$setup(SLOAD, posedge CLK, `SYNCSETUP);
$setup(SDATA, posedge CLK, `SYNCSETUP);
endspecify
initial begin
// Altera flops initialise to zero.
Q = 0;
end
always @(posedge CLK) begin
// Clock-enable
if (ENA) begin
// Synchronous clear
if (SCLR) Q <= 0;
// Synchronous load
else if (SLOAD) Q <= SDATA;
else Q <= DATAIN;
end
end
endmodule
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