diff options
Diffstat (limited to 'inband_lib/channel_ram.v')
| -rwxr-xr-x | inband_lib/channel_ram.v | 175 |
1 files changed, 84 insertions, 91 deletions
diff --git a/inband_lib/channel_ram.v b/inband_lib/channel_ram.v index 60450f02d..9621246c5 100755 --- a/inband_lib/channel_ram.v +++ b/inband_lib/channel_ram.v @@ -1,114 +1,107 @@ module channel_ram - ( // System - input txclk, - input reset, + ( // System + input txclk, input reset, + // USB side + input [31:0] datain, input WR, input WR_done, output have_space, + // Reader side + output [31:0] dataout, input RD, input RD_done, output packet_waiting); - // USB side - input [31:0] datain, - input WR, - input WR_done, - output have_space, - - // Reader side - output [31:0] dataout, - input RD, - input RD_done, - output packet_waiting); - - reg [6:0] wr_addr, rd_addr; - reg [1:0] which_ram_wr, which_ram_rd; - reg [2:0] nb_packets; + reg [6:0] wr_addr, rd_addr; + reg [1:0] which_ram_wr, which_ram_rd; + reg [2:0] nb_packets; - reg [31:0] ram0 [0:127]; - reg [31:0] ram1 [0:127]; - reg [31:0] ram2 [0:127]; - reg [31:0] ram3 [0:127]; + reg [31:0] ram0 [0:127]; + reg [31:0] ram1 [0:127]; + reg [31:0] ram2 [0:127]; + reg [31:0] ram3 [0:127]; - reg [31:0] dataout0; - reg [31:0] dataout1; - reg [31:0] dataout2; - reg [31:0] dataout3; + reg [31:0] dataout0; + reg [31:0] dataout1; + reg [31:0] dataout2; + reg [31:0] dataout3; - wire wr_done_int; - wire rd_done_int; - wire [6:0] rd_addr_final; - wire [1:0] which_ram_rd_final; + wire wr_done_int; + wire rd_done_int; + wire [6:0] rd_addr_final; + wire [1:0] which_ram_rd_final; - // USB side - always @(posedge txclk) - if(WR & (which_ram_wr == 2'd0)) ram0[wr_addr] <= datain; + // USB side + always @(posedge txclk) + if(WR & (which_ram_wr == 2'd0)) ram0[wr_addr] <= datain; - always @(posedge txclk) - if(WR & (which_ram_wr == 2'd1)) ram1[wr_addr] <= datain; + always @(posedge txclk) + if(WR & (which_ram_wr == 2'd1)) ram1[wr_addr] <= datain; - always @(posedge txclk) - if(WR & (which_ram_wr == 2'd2)) ram2[wr_addr] <= datain; + always @(posedge txclk) + if(WR & (which_ram_wr == 2'd2)) ram2[wr_addr] <= datain; - always @(posedge txclk) - if(WR & (which_ram_wr == 2'd3)) ram3[wr_addr] <= datain; + always @(posedge txclk) + if(WR & (which_ram_wr == 2'd3)) ram3[wr_addr] <= datain; assign wr_done_int = ((WR && (wr_addr == 7'd127)) || WR_done); - always @(posedge txclk) - if(reset) - wr_addr <= 0; - else if (WR_done) - wr_addr <= 0; - else if (WR) - wr_addr <= wr_addr + 7'd1; + always @(posedge txclk) + if(reset) + wr_addr <= 0; + else if (WR_done) + wr_addr <= 0; + else if (WR) + wr_addr <= wr_addr + 7'd1; - always @(posedge txclk) - if(reset) - which_ram_wr <= 0; - else if (wr_done_int) - which_ram_wr <= which_ram_wr + 2'd1; + always @(posedge txclk) + if(reset) + which_ram_wr <= 0; + else if (wr_done_int) + which_ram_wr <= which_ram_wr + 2'd1; - assign have_space = (nb_packets < 3'd3); + assign have_space = (nb_packets < 3'd3); - // Reader side - // short hand fifo - // rd_addr_final is what rd_addr is going to be next clock cycle - // which_ram_rd_final is what which_ram_rd is going to be next clock cycle - always @(posedge txclk) dataout0 <= ram0[rd_addr_final]; - always @(posedge txclk) dataout1 <= ram1[rd_addr_final]; - always @(posedge txclk) dataout2 <= ram2[rd_addr_final]; - always @(posedge txclk) dataout3 <= ram3[rd_addr_final]; + // Reader side + // short hand fifo + // rd_addr_final is what rd_addr is going to be next clock cycle + // which_ram_rd_final is what which_ram_rd is going to be next clock cycle + always @(posedge txclk) dataout0 <= ram0[rd_addr_final]; + always @(posedge txclk) dataout1 <= ram1[rd_addr_final]; + always @(posedge txclk) dataout2 <= ram2[rd_addr_final]; + always @(posedge txclk) dataout3 <= ram3[rd_addr_final]; - assign dataout = (which_ram_rd_final[1]) ? - (which_ram_rd_final[0] ? dataout3 : dataout2) : - (which_ram_rd_final[0] ? dataout1 : dataout0); + assign dataout = (which_ram_rd_final[1]) ? + (which_ram_rd_final[0] ? dataout3 : dataout2) : + (which_ram_rd_final[0] ? dataout1 : dataout0); - //RD_done is the only way to signal the end of one packet - assign rd_done_int = RD_done; + //RD_done is the only way to signal the end of one packet + assign rd_done_int = RD_done; - always @(posedge txclk) - if (reset) - rd_addr <= 0; - else if (RD_done) - rd_addr <= 0; - else if (RD) rd_addr <= rd_addr + 7'd1; + always @(posedge txclk) + if (reset) + rd_addr <= 0; + else if (RD_done) + rd_addr <= 0; + else if (RD) + rd_addr <= rd_addr + 7'd1; - assign rd_addr_final = (reset|RD_done) ? (6'd0) : - ((RD)?(rd_addr+7'd1):rd_addr); - always @(posedge txclk) - if (reset) - which_ram_rd <= 0; - else if (rd_done_int) - which_ram_rd <= which_ram_rd + 2'd1; + assign rd_addr_final = (reset|RD_done) ? (6'd0) : + ((RD)?(rd_addr+7'd1):rd_addr); + + always @(posedge txclk) + if (reset) + which_ram_rd <= 0; + else if (rd_done_int) + which_ram_rd <= which_ram_rd + 2'd1; - assign which_ram_rd_final = (reset) ? (2'd0): + assign which_ram_rd_final = (reset) ? (2'd0): ((rd_done_int) ? (which_ram_rd + 2'd1) : which_ram_rd); - //packet_waiting is set to zero if rd_done_int is high - //because there is no guarantee that nb_packets will be pos. - //assign packet_waiting = (nb_packets != 0) & (~rd_done_int); - assign packet_waiting = (nb_packets > 1) | ((nb_packets == 1)&(~rd_done_int)); - always @(posedge txclk) - if (reset) - nb_packets <= 0; - else if (wr_done_int & ~rd_done_int) - nb_packets <= nb_packets + 3'd1; - else if (rd_done_int & ~wr_done_int) - nb_packets <= nb_packets - 3'd1; + //packet_waiting is set to zero if rd_done_int is high + //because there is no guarantee that nb_packets will be pos. + + assign packet_waiting = (nb_packets > 1) | ((nb_packets == 1)&(~rd_done_int)); + always @(posedge txclk) + if (reset) + nb_packets <= 0; + else if (wr_done_int & ~rd_done_int) + nb_packets <= nb_packets + 3'd1; + else if (rd_done_int & ~wr_done_int) + nb_packets <= nb_packets - 3'd1; -endmodule
\ No newline at end of file +endmodule |