X-Git-Url: http://wien.tomnetworks.com/gitweb/?a=blobdiff_plain;ds=sidebyside;f=cpu%2Fsrc%2Fwriteback_stage_b.vhd;fp=cpu%2Fsrc%2Fwriteback_stage_b.vhd;h=6f2c9c47393ce4223ba207e3fe9a44e1753efb2c;hb=3e9337b7a4d81fb059f90716d7df9aa3bec9d719;hp=8c13049009229ccac1826458c1ae41d9df3b989c;hpb=f79b90fff6c5992d835bcdac3252fa023adf4538;p=calu.git

diff --git a/cpu/src/writeback_stage_b.vhd b/cpu/src/writeback_stage_b.vhd
index 8c13049..6f2c9c4 100644
--- a/cpu/src/writeback_stage_b.vhd
+++ b/cpu/src/writeback_stage_b.vhd
@@ -21,7 +21,7 @@ signal ext_uart,ext_timer,ext_gpmp,ext_7seg :  extmod_rec;
 
 signal sel_nxt, dmem_we, bus_rx :std_logic;
 
-
+signal calc_mem_res : gp_register_t;
 
 begin
 
@@ -104,25 +104,25 @@ begin
 	wb_reg_nxt.hword <= hword;
 	wb_reg_nxt.byte_s <= byte_s;
 
-	regfile_val <= result; --(others => '0');
+	calc_mem_res <= result; --(others => '0');
 
 	if (wb_reg.dmem_en = '1' and wb_reg.dmem_write_en = '0') then	-- ram read operation --alu_jmp = '0' and 
-		regfile_val <= data_ram_read;
+		calc_mem_res <= data_ram_read;
 		if (wb_reg.hword = '1') then
-			regfile_val <= (others => '0');
+			calc_mem_res <= (others => '0');
 			if (wb_reg.address(1) = '1') then
-				regfile_val(15 downto 0) <= data_ram_read(31 downto 16);
+				calc_mem_res(15 downto 0) <= data_ram_read(31 downto 16);
 			else
-				regfile_val(15 downto 0) <= data_ram_read(15 downto 0);
+				calc_mem_res(15 downto 0) <= data_ram_read(15 downto 0);
 			end if;
 		end if;
 		if (wb_reg.byte_s = '1') then
-			regfile_val <= (others => '0');
+			calc_mem_res <= (others => '0');
 			case wb_reg.address(1 downto 0) is
-				when "00" => regfile_val(7 downto 0) <= data_ram_read(7 downto 0);
-				when "01" => regfile_val(7 downto 0) <= data_ram_read(15 downto 8);
-				when "10" => regfile_val(7 downto 0) <= data_ram_read(23 downto 16);
-				when "11" => regfile_val(7 downto 0) <= data_ram_read(31 downto 24);
+				when "00" => calc_mem_res(7 downto 0) <= data_ram_read(7 downto 0);
+				when "01" => calc_mem_res(7 downto 0) <= data_ram_read(15 downto 8);
+				when "10" => calc_mem_res(7 downto 0) <= data_ram_read(23 downto 16);
+				when "11" => calc_mem_res(7 downto 0) <= data_ram_read(31 downto 24);
 				when others => null;
 			end case;
 		end if;	
@@ -159,7 +159,7 @@ end process;
 
 
 
-out_logic: process(write_en, result_addr, wb_reg, alu_jmp, wb_reg_nxt)
+out_logic: process(write_en, result_addr, wb_reg, alu_jmp, wb_reg_nxt, data_ram_read_ext, calc_mem_res)
 
 begin	
 	reg_we <= (write_en or (wb_reg.dmem_en and not(wb_reg.dmem_write_en))) and not(alu_jmp);
@@ -172,12 +172,19 @@ begin
 		data_addr(DATA_ADDR_WIDTH+1 downto 0) <= wb_reg_nxt.address(DATA_ADDR_WIDTH+1 downto 0);
 		dmem_we <= wb_reg_nxt.dmem_write_en;
 	end if;
+	
+	regfile_val <= calc_mem_res;
+
+	if (wb_reg.address(31 downto 4) = EXT_UART_ADDR) then
+		regfile_val <= data_ram_read_ext;
+	end if;
 end process;
 
 
-addr_de_mult: process(wb_reg_nxt.address, ram_data, wb_reg,sel_nxt,wb_reg_nxt.dmem_write_en)
+addr_de_mult: process(wb_reg_nxt, ram_data, wb_reg,sel_nxt)
 
 begin
+
   ext_uart.sel <='0';
   ext_uart.wr_en <= wb_reg_nxt.dmem_write_en;
   ext_uart.byte_en <= (others => '0');
@@ -203,19 +210,19 @@ begin
   ext_gpmp.addr <= (others => '0');
    -- wenn ich hier statt dem 4rer die konstante nehme dann gibts an fehler wegen nicht lokaler variable -.-
  case wb_reg_nxt.address(31 downto 4) is
-	when EXT_UART_ADDR => 
-		ext_uart.sel <='1';
-		ext_uart.wr_en <= wb_reg_nxt.dmem_write_en;
-  		ext_uart.data <= ram_data;
-		ext_uart.addr <= wb_reg_nxt.address(31 downto 2);
-		case wb_reg_nxt.address(1 downto 0) is
-				when "00" => ext_uart.byte_en <= "0001";
-				when "01" => ext_uart.byte_en <= "0010";
-				when "10" => ext_uart.byte_en <= "0100";
-				--when "11" => ext_uart.byte_en <= "1000";
-				when "11" => ext_uart.byte_en <= "1111";
-				when others => null;
-			end case;
+--	when EXT_UART_ADDR => 
+--		ext_uart.sel <='1';
+--		ext_uart.wr_en <= wb_reg_nxt.dmem_write_en;
+--  		ext_uart.data <= ram_data;
+--		ext_uart.addr <= wb_reg_nxt.address(31 downto 2);
+--		case wb_reg_nxt.address(1 downto 0) is
+--				when "00" => ext_uart.byte_en <= "0001";
+--				when "01" => ext_uart.byte_en <= "0010";
+--				when "10" => ext_uart.byte_en <= "0100";
+--				--when "11" => ext_uart.byte_en <= "1000";
+--				when "11" => ext_uart.byte_en <= "1111";
+--				when others => null;
+--			end case;
 
 	when EXT_7SEG_ADDR => 
 		ext_7seg.sel <='1';