diff --git a/experiments/primitive_ram/Top.bsv b/experiments/primitive_ram/Top.bsv
index 862eba0..14993b3 100644
--- a/experiments/primitive_ram/Top.bsv
+++ b/experiments/primitive_ram/Top.bsv
@@ -2,13 +2,19 @@ package Top;
 
 import ECP5_RAM::*;
 
-(* synthesize *)
-module mkTop(ECP5_EBRCorePort#(Bit#(12), Bit#(8)));
-   let clk <- exposeCurrentClock;
-   let rstN <- exposeCurrentReset;
+(* always_enabled *)
+interface Top;
+   method Action put(UInt#(3) select, Bool write, Bit#(12) address, Bit#(4) data);
+   method Bit#(4) read();
+endinterface
 
-   ECP5_EBRPortConfig cfg = defaultValue;
-   ECP5_EBRCore#(Bit#(12), Bit#(8), UInt#(12), UInt#(8)) ram <- mkECP5_EBRCoreByte(cfg, cfg);
+(* synthesize *)
+module mkTop(Clock extClk, Reset extRst, Top ifc);
+   ECP5_EBRPortConfig cfgA = defaultValue;
+   cfgA.clk = tagged Valid extClk;
+   cfgA.rstN = tagged Valid extRst;
+   ECP5_EBRPortConfig cfgB = defaultValue;
+   ECP5_EBRCore#(Bit#(12), Bit#(4), UInt#(12), UInt#(4)) ram <- mkECP5_EBRCore(cfgA, cfgB);
 
    method put = ram.portA.put;
    method read = ram.portA.read;