From 5a2c8fa2934a3eca5207cd58026465f847358cdf Mon Sep 17 00:00:00 2001
From: nikitalita <69168929+nikitalita@users.noreply.github.com>
Date: Wed, 22 May 2024 20:01:31 -0700
Subject: [PATCH] Fix NES controllers

---
 src/controller_snes.v | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/controller_snes.v b/src/controller_snes.v
index 61f4620..fea99af 100644
--- a/src/controller_snes.v
+++ b/src/controller_snes.v
@@ -111,7 +111,14 @@ always @(posedge clk) begin
                 bits <= bits + 1;
                 if (bits == 4'd15) begin     // scan complete
                     state <= 3;
-                    buttons <= buttons_buf[11:0];
+                    // check if buttons_buf[15:12] are 0; if not, this is an NES controller
+                    if (buttons_buf[15:12] != 4'b0000) begin
+                        // NES controller
+                        buttons <= {0, 0, 0, 0, buttons_buf[7:0]};
+                    end else begin
+                        // SNES controller
+                        buttons <= buttons_buf[11:0];
+                    end
                 end else
                     state <= 1;
             end