alu update

[motonesfpga/motonesfpga.git] / de1_nes / cpu / alu.vhd

diff --git a/de1_nes/cpu/alu.vhd b/de1_nes/cpu/alu.vhd
index 6b915bc..83d1e2e 100644 (file)
--- a/de1_nes/cpu/alu.vhd
+++ b/de1_nes/cpu/alu.vhd
@@ -278,6 +278,7 @@ begin
             tmp_buf_we_n <= '0';
             tmp_reg_in <= bal;
         elsif (addr_cycle = ADDR_T3) then
+            tmp_buf_we_n <= '1';
 
             ---add x reg.
             a_sel <= ADDR_ADC;
@@ -285,10 +286,6 @@ begin
             addr2 <= index_bus;
             addr_c_in <= '0';
 
-            --save base addr.
-            tmp_buf_we_n <= '0';
-            tmp_reg_in <= addr_out;
-
             --output @IAL+x
             abh <= "00000000";
             abl <= addr_out;
@@ -301,11 +298,13 @@ begin
             al_buf_we_n <= '1';
             tmp_buf_we_n <= '1';
 
-            ---increment.
-            a_sel <= ADDR_INC;
-            addr1 <= tmp_reg;
+            ---add x+1 reg.
+            a_sel <= ADDR_ADC;
+            addr1 <= tmp_reg + '1';
+            addr2 <= index_bus;
+            addr_c_in <= '0';
 
-            --output @IAL+x
+            --output @IAL+x+1
             abh <= "00000000";
             abl <= addr_out;