diff --git a/lib/CPUs/JCpu/sim/tb_mul8x8.fdo b/lib/CPUs/JCpu/sim/tb_mul8x8.fdo
index f727dff..5a852a4 100644
--- a/lib/CPUs/JCpu/sim/tb_mul8x8.fdo
+++ b/lib/CPUs/JCpu/sim/tb_mul8x8.fdo
@@ -5,6 +5,7 @@ vcom -explicit  -93 "../src/core/cpu_pkg.vhd"
 vcom -explicit  -93 "../src/core/stack_ctrl.vhd"
 vcom -explicit  -93 "../src/core/reg_dual.vhd"
 vcom -explicit  -93 "../src/core/chipram.vhd"
+vcom -explicit  -93 "../src/core/chipreg.vhd"
 vcom -explicit  -93 "../src/core/pc.vhd"
 vcom -explicit  -93 "../src/core/dpath_ctrl.vhd"
 vcom -explicit  -93 "../src/core/int_ctrl.vhd"