diff --git a/hal/src/main/native/sim/PortsInternal.h b/hal/src/main/native/sim/PortsInternal.h
index 2d1a205e27..190573b6ae 100644
--- a/hal/src/main/native/sim/PortsInternal.h
+++ b/hal/src/main/native/sim/PortsInternal.h
@@ -7,6 +7,7 @@
 #include <stdint.h>
 
 namespace hal {
+constexpr int32_t kAccelerometers = 1;
 constexpr int32_t kNumAccumulators = 2;
 constexpr int32_t kNumAnalogTriggers = 8;
 constexpr int32_t kNumAnalogInputs = 8;
@@ -18,6 +19,7 @@ constexpr int32_t kNumDigitalChannels = 31;
 constexpr int32_t kNumPWMChannels = 20;
 constexpr int32_t kNumDigitalPWMOutputs = 6;
 constexpr int32_t kNumEncoders = 8;
+constexpr int32_t kI2CPorts = 2;
 constexpr int32_t kNumInterrupts = 8;
 constexpr int32_t kNumRelayChannels = 8;
 constexpr int32_t kNumRelayHeaders = kNumRelayChannels / 2;
@@ -27,8 +29,13 @@ constexpr int32_t kNumCTREPDPModules = 63;
 constexpr int32_t kNumCTREPDPChannels = 16;
 constexpr int32_t kNumREVPDHModules = 63;
 constexpr int32_t kNumREVPDHChannels = 24;
+constexpr int32_t kNumPDSimModules = kNumREVPDHModules;
+constexpr int32_t kNumPDSimChannels = kNumREVPDHChannels;
 constexpr int32_t kNumDutyCycles = 8;
 constexpr int32_t kNumAddressableLEDs = 1;
 constexpr int32_t kNumREVPHModules = 63;
 constexpr int32_t kNumREVPHChannels = 16;
+constexpr int32_t kSPIAccelerometers = 5;
+constexpr int32_t kSPIPorts = 5;
+
 }  // namespace hal
diff --git a/hal/src/main/native/sim/mockdata/AccelerometerData.cpp b/hal/src/main/native/sim/mockdata/AccelerometerData.cpp
index 8ed4d780e0..92848309a3 100644
--- a/hal/src/main/native/sim/mockdata/AccelerometerData.cpp
+++ b/hal/src/main/native/sim/mockdata/AccelerometerData.cpp
@@ -9,7 +9,7 @@ using namespace hal;
 
 namespace hal::init {
 void InitializeAccelerometerData() {
-  static AccelerometerData sad[1];
+  static AccelerometerData sad[kAccelerometers];
   ::hal::SimAccelerometerData = sad;
 }
 }  // namespace hal::init
diff --git a/hal/src/main/native/sim/mockdata/I2CData.cpp b/hal/src/main/native/sim/mockdata/I2CData.cpp
index 0ac813d178..d3b7db61cd 100644
--- a/hal/src/main/native/sim/mockdata/I2CData.cpp
+++ b/hal/src/main/native/sim/mockdata/I2CData.cpp
@@ -9,7 +9,7 @@ using namespace hal;
 
 namespace hal::init {
 void InitializeI2CData() {
-  static I2CData sid[2];
+  static I2CData sid[kI2CPorts];
   ::hal::SimI2CData = sid;
 }
 }  // namespace hal::init
diff --git a/hal/src/main/native/sim/mockdata/PowerDistributionDataInternal.h b/hal/src/main/native/sim/mockdata/PowerDistributionDataInternal.h
index 4876dbdfda..cb3e4b38e2 100644
--- a/hal/src/main/native/sim/mockdata/PowerDistributionDataInternal.h
+++ b/hal/src/main/native/sim/mockdata/PowerDistributionDataInternal.h
@@ -9,8 +9,6 @@
 #include "hal/simulation/SimDataValue.h"
 
 namespace hal {
-constexpr int32_t kNumPDSimModules = hal::kNumREVPDHModules;
-constexpr int32_t kNumPDSimChannels = hal::kNumREVPDHChannels;
 
 class PowerDistributionData {
   HAL_SIMDATAVALUE_DEFINE_NAME(Initialized)
diff --git a/hal/src/main/native/sim/mockdata/SPIAccelerometerData.cpp b/hal/src/main/native/sim/mockdata/SPIAccelerometerData.cpp
index 6c5f3411b9..0ec10cf8a2 100644
--- a/hal/src/main/native/sim/mockdata/SPIAccelerometerData.cpp
+++ b/hal/src/main/native/sim/mockdata/SPIAccelerometerData.cpp
@@ -9,7 +9,7 @@ using namespace hal;
 
 namespace hal::init {
 void InitializeSPIAccelerometerData() {
-  static SPIAccelerometerData ssad[5];
+  static SPIAccelerometerData ssad[kSPIAccelerometers];
   ::hal::SimSPIAccelerometerData = ssad;
 }
 }  // namespace hal::init
diff --git a/hal/src/main/native/sim/mockdata/SPIData.cpp b/hal/src/main/native/sim/mockdata/SPIData.cpp
index 9499b9bbe7..82f7650aba 100644
--- a/hal/src/main/native/sim/mockdata/SPIData.cpp
+++ b/hal/src/main/native/sim/mockdata/SPIData.cpp
@@ -9,7 +9,7 @@ using namespace hal;
 
 namespace hal::init {
 void InitializeSPIData() {
-  static SPIData ssd[5];
+  static SPIData ssd[kSPIPorts];
   ::hal::SimSPIData = ssd;
 }
 }  // namespace hal::init