Add an interrupt ack, so that interrupts are cleared automatically. This fixes APOCAL...

diff --git a/GBZ80Core.v b/GBZ80Core.v
index 3c2f7702aaa1c9e507232c435029c0a4456f48cf..29aab5203b4c24c909f6cfab270ffc9b0ecbeaff 100644 (file)
--- a/GBZ80Core.v
+++ b/GBZ80Core.v
@@ -152,7 +152,7 @@ module GBZ80Core(
        inout [15:0] bus1address,       /* BUS_* is latched on STATE_FETCH. */
        inout [7:0] bus1data,
        inout bus1wr, bus1rd,
-       input irq, input [7:0] jaddr,
+       input irq, output reg irqack, input [7:0] jaddr,
        output reg [1:0] state);
 
 //     reg [1:0] state;                                        /* State within this bus cycle (see STATE_*). */
@@ -282,6 +282,7 @@ module GBZ80Core(
                cycle <= 0;
                twobyte <= 0;
                bootstrap_enb <= 1;
+               irqack <= 0;
        end
 
        always @(negedge clk)   /* Set things up at the negedge to prepare for the posedge. */
@@ -341,8 +342,10 @@ module GBZ80Core(
                        state <= `STATE_EXECUTE;
                end
                `STATE_EXECUTE: begin
+               `ifdef isim
                        if (opcode[7:0] === 8'bxxxxxxxx)
                                $stop;
+               `endif
                        casex (opcode)
                        `define EXECUTE
                        `include "allinsns.v"

diff --git a/Interrupt.v b/Interrupt.v
index 26861462d1d1dc07bf5038aacee714b282667b9e..201c328979d64f8abd8908e8e64c9c4974669102 100644 (file)
--- a/Interrupt.v
+++ b/Interrupt.v
@@ -13,6 +13,7 @@ module Interrupt(
        input serial,
        input buttons,
        output master,
+       input ack,
        output [7:0] jaddr);
 
        wire [7:0] iflag = {3'b0,buttons,serial,tovf,lcdc,vblank};
@@ -45,7 +46,14 @@ module Interrupt(
                        `ADDR_IE : begin imask <= data; ihold <= ihold | iflag; end
                        endcase
                        
-               end
+               end else if (ack)
+                       ihold <= ihold &
+                               (imasked[0] ? 8'b11111110 :
+                                imasked[1] ? 8'b11111101 :
+                                imasked[2] ? 8'b11111011 :
+                                imasked[3] ? 8'b11110111 :
+                                imasked[4] ? 8'b11101111 :
+                                8'b11111111);
                else
                        ihold <= ihold | iflag;
                rdlatch <= rd;

diff --git a/System.v b/System.v
index c2e892bd1a4029a85cf603b84a6b4fbcee8df331..62f976be7dc3d4f8062de7ad4c07d88131d435a4 100644 (file)
--- a/System.v
+++ b/System.v
@@ -265,6 +265,7 @@ module CoreTop(
        wire irq, tmrirq, lcdcirq, vblankirq;
        wire [7:0] jaddr;
        wire [1:0] state;
+       wire ack;
        
        GBZ80Core core(
                .clk(clk),
@@ -277,6 +278,7 @@ module CoreTop(
                .bus1wr(wr[1]),
                .bus1rd(rd[1]),
                .irq(irq),
+               .irqack(ack),
                .jaddr(jaddr),
                .state(state));
        
@@ -415,6 +417,7 @@ module CoreTop(
                .serial(1'b0),
                .buttons(1'b0),
                .master(irq),
+               .ack(ack),
                .jaddr(jaddr));
        
        Soundcore sound(

diff --git a/insn_vop_intr.v b/insn_vop_intr.v
index 5cb40e1f6f5b8e2d99df0a6cf53c02147fe9baf1..ce0bcf8acb5f91bbaf9b645f412da983f63825c6 100644 (file)
--- a/insn_vop_intr.v
+++ b/insn_vop_intr.v
@@ -3,7 +3,10 @@
                case (cycle)
                0:      `EXEC_WRITE(`_SP - 1, `_PCH)
                1:      `EXEC_WRITE(`_SP - 2, `_PCL)
-               2:      `EXEC_NEWCYCLE
+               2:      begin
+                               irqack <= 1;
+                               `EXEC_NEWCYCLE
+                       end
                endcase
        end
 `endif
@@ -16,6 +19,7 @@
                2:      begin
                                ie <= 0;
                                `_PC <= {8'b0, jaddr};
+                               irqack <= 0;    // Must be at the same time as we latch jaddr, or we race!
                                `_SP <= `_SP - 2;
                        end
                endcase