diff --git a/cheriot/cheriot_state.h b/cheriot/cheriot_state.h
index 2b082b9..31df622 100644
--- a/cheriot/cheriot_state.h
+++ b/cheriot/cheriot_state.h
@@ -170,6 +170,7 @@
 class CheriotState : public generic::ArchState {
  public:
   static constexpr int kVersion0Dot5 = 50;
+  static constexpr int kVersion1Dot0 = 100;
   static int constexpr kCapRegQueueSizeMask = 0x11;
   static constexpr uint32_t kCheriExceptionCode = 0x1c;
   static constexpr char kCregPrefix[] = "c";
@@ -436,8 +437,8 @@
  private:
   InterruptCode PickInterrupt(uint32_t interrupts);
   // Core version. Expressed as an integer where as version * 100. Thus
-  // version 1.0 is 100, and 1.5 is 150. Default is 0.5 (or 50).
-  int core_version_ = kVersion0Dot5;
+  // version 1.0 is 100, and 1.5 is 150. Default is 1.0 (or 100).
+  int core_version_ = kVersion1Dot0;
   // A map from register name to entry in the mtval register.
   absl::flat_hash_map<std::string, uint32_t> cap_index_map_;
   // These are root capabilities
diff --git a/cheriot/mpact_cheriot.cc b/cheriot/mpact_cheriot.cc
index edc3006..312e334 100644
--- a/cheriot/mpact_cheriot.cc
+++ b/cheriot/mpact_cheriot.cc
@@ -82,7 +82,7 @@
 using ::mpact::sim::util::TaggedMemoryUseProfiler;
 
 // Flat to specify core version.
-ABSL_FLAG(int, core_version, 50, "Core version");
+ABSL_FLAG(int, core_version, 100, "Core version");
 // Flags for specifying interactive mode.
 ABSL_FLAG(bool, i, false, "Interactive mode");
 ABSL_FLAG(bool, interactive, false, "Interactive mode");
diff --git a/cheriot/test/riscv_cheriot_instructions_test.cc b/cheriot/test/riscv_cheriot_instructions_test.cc
index bf66129..60aeb85 100644
--- a/cheriot/test/riscv_cheriot_instructions_test.cc
+++ b/cheriot/test/riscv_cheriot_instructions_test.cc
@@ -100,7 +100,7 @@
 
 constexpr int kDataSeal10 = 10;
 constexpr int kInstSizeNormal = 4;
-
+constexpr int kVersion0Dot5 = 50;
 constexpr int kVersion1Dot0 = 100;
 
 // Test fixture.
@@ -622,6 +622,8 @@
   AppendCapabilityOperands(inst(), {kC1}, {kC3});
   state()->pcc()->set_address(inst()->address());
   c1_reg()->set_address(0x200);
+  // Set core version to 0.5.
+  state()->set_core_version(kVersion0Dot5);
   // Set interrupt enable to true.
   state()->mstatus()->set_mie(1);
   state()->mstatus()->Submit();
@@ -723,6 +725,8 @@
   c1_reg()->SetBounds(kInstAddress, 0x400);
   // Set offset.
   c2_reg()->set_address(0x100);
+  // Set core version to 0.5.
+  state()->set_core_version(kVersion0Dot5);
   // Set interrupt enable to true.
   state()->mstatus()->set_mie(1);
   state()->mstatus()->Submit();