Only run selector logic if we need a new selection next cycle.

1 files changed, 4 insertions, 1 deletions

diff --git a/hdl/mem_arbiter.sv b/hdl/mem_arbiter.sv
index 1404a54..e39317d 100644
--- a/hdl/mem_arbiter.sv
+++ b/hdl/mem_arbiter.sv
@@ -32,12 +32,15 @@ module mem_arbiter
                 hold_valid[i] = 0;
             selector = 0;
         end else begin
+            automatic bit selector_stale = 0;
+
             if (ram_ready) ram_valid = 0;
 
             if (!ram_valid && hold_valid[selector]) begin
                 ram_valid = 1;
                 ram_data = hold_data[selector];
                 hold_valid[selector] = 0;
+                selector_stale = 1;
             end
 
             if (hold_valid == 0) begin
@@ -59,7 +62,7 @@ module mem_arbiter
                 end
             end
 
-            if (hold_valid != 0) begin
+            if (hold_valid != 0 && (selector_stale || !ram_valid)) begin
                 for (int i = 0; i < `NUM_PDPS+1; ++i) begin
                     automatic int j = selector + i;
                     if (j > `NUM_PDPS)