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module omsp_dbg_uart (dbg_clk, dbg_rst, mem_burst, cmd_valid);
input dbg_clk;
input dbg_rst;
input mem_burst;
output cmd_valid;
reg [2:0] uart_state;
reg [2:0] uart_state_nxt;
wire xfer_done;
parameter RX_SYNC = 3'h0;
parameter RX_CMD = 3'h1;
parameter RX_DATA = 3'h2;
always @(uart_state or mem_burst)
case (uart_state)
RX_SYNC : uart_state_nxt = RX_CMD;
RX_CMD : uart_state_nxt = mem_burst ? RX_DATA : RX_SYNC;
RX_DATA : uart_state_nxt = RX_SYNC;
default : uart_state_nxt = RX_CMD;
endcase
always @(posedge dbg_clk or posedge dbg_rst)
if (dbg_rst) uart_state <= RX_SYNC;
else if (xfer_done | mem_burst) uart_state <= uart_state_nxt;
assign cmd_valid = (uart_state==RX_CMD) & xfer_done;
assign xfer_done = uart_state!=RX_SYNC;
endmodule
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