diff --git a/Firmware/mmu2/registers.h b/Firmware/mmu2/registers.h
new file mode 100644
index 000000000..489facc39
--- /dev/null
+++ b/Firmware/mmu2/registers.h
@@ -0,0 +1,40 @@
+#pragma once
+
+// Register map for MMU
+enum class Register : uint8_t
+{
+    Project_Major = 0x00,
+    Project_Minor = 0x01,
+    Project_Revision = 0x02,
+    Project_Build_Number = 0x03,
+    MMU_Errors = 0x04,
+    Current_Progress_Code = 0x05,
+    Current_Error_Code = 0x06,
+    Filament_State = 0x07,
+    FINDA_State = 0x08,
+    FSensor_State = 0x09,
+    Motor_Mode = 0x0A,
+    Extra_Load_Distance = 0x0B,
+    FSensor_Unload_Check_Distance = 0xC,
+    Pulley_Unload_Feedrate = 0x0D,
+    Pulley_Acceleration = 0x0E,
+    Selector_Acceleration = 0x0F,
+    Idler_Acceleration = 0x10,
+    Pulley_Load_Feedrate = 0x11,
+    Selector_Nominal_Feedrate = 0x12,
+    Idler_Nominal_Feedrate = 0x13,
+    Pulley_Slow_Feedrate = 0x14,
+    Selector_Homing_Feedrate = 0x15,
+    Idler_Homing_Feedrate = 0x16,
+    Pulley_sg_thrs_R = 0x17,
+    Selector_sg_thrs_R = 0x18,
+    Idler_sg_thrs_R = 0x19,
+    Get_Pulley_Position = 0x1A,
+    Set_Get_Selector_Slot = 0x1B,
+    Set_Get_Idler_Slot = 0x1C,
+    Set_Get_Selector_Cut_iRun = 0x1D,
+    Set_Get_Pulley_iRun = 0x1E,
+    Set_Get_Selector_iRun = 0x1F,
+    Set_Get_Idler_iRun = 0x20,
+    Reserved = 0x21,
+};
diff --git a/Firmware/mmu2_protocol_logic.cpp b/Firmware/mmu2_protocol_logic.cpp
index d7be95648..82b28b2f1 100644
--- a/Firmware/mmu2_protocol_logic.cpp
+++ b/Firmware/mmu2_protocol_logic.cpp
@@ -26,20 +26,20 @@ namespace MMU2 {
 /// To save space a "dumb" solution was chosen + a few static_assert checks in errors_list.h preventing the code from compiling when the string doesn't match.
 static constexpr uint8_t supportedMmuFWVersion[3] PROGMEM = { mmuVersionMajor, mmuVersionMinor, mmuVersionPatch };
 
-const uint8_t ProtocolLogic::regs8Addrs[ProtocolLogic::regs8Count] PROGMEM = {
-    8,    // FINDA state
-    0x1b, // Selector slot
-    0x1c, // Idler slot
+const Register ProtocolLogic::regs8Addrs[ProtocolLogic::regs8Count] PROGMEM = {
+    Register::FINDA_State,    // FINDA state
+    Register::Set_Get_Selector_Slot, // Selector slot
+    Register::Set_Get_Idler_Slot, // Idler slot
 };
 
-const uint8_t ProtocolLogic::regs16Addrs[ProtocolLogic::regs16Count] PROGMEM = {
-    4,    // MMU errors - aka statistics
-    0x1a, // Pulley position [mm]
+const Register ProtocolLogic::regs16Addrs[ProtocolLogic::regs16Count] PROGMEM = {
+    Register::MMU_Errors,    // MMU errors - aka statistics
+    Register::Get_Pulley_Position, // Pulley position [mm]
 };
 
-const uint8_t ProtocolLogic::initRegs8Addrs[ProtocolLogic::initRegs8Count] PROGMEM = {
-    0x0b, // extra load distance [mm]
-    0x14, // pulley slow feedrate [mm/s]
+const Register ProtocolLogic::initRegs8Addrs[ProtocolLogic::initRegs8Count] PROGMEM = {
+    Register::Extra_Load_Distance, // extra load distance [mm]
+    Register::Pulley_Slow_Feedrate, // pulley slow feedrate [mm/s]
 };
 
 void ProtocolLogic::CheckAndReportAsyncEvents() {
diff --git a/Firmware/mmu2_protocol_logic.h b/Firmware/mmu2_protocol_logic.h
index 1a13bbe66..251674ce8 100644
--- a/Firmware/mmu2_protocol_logic.h
+++ b/Firmware/mmu2_protocol_logic.h
@@ -6,6 +6,7 @@
 #include "mmu2/error_codes.h"
 #include "mmu2/progress_codes.h"
 #include "mmu2/buttons.h"
+#include "mmu2/registers.h"
 #include "mmu2_protocol.h"
 
 // #include <array> std array is not available on AVR ... we need to "fake" it
@@ -372,19 +373,19 @@ private:
     // 8bit registers
     static constexpr uint8_t regs8Count = 3;
     static_assert(regs8Count > 0); // code is not ready for empty lists of registers
-    static const uint8_t regs8Addrs[regs8Count] PROGMEM;
+    static const Register regs8Addrs[regs8Count] PROGMEM;
     uint8_t regs8[regs8Count] = { 0, 0, 0 };
 
     // 16bit registers
     static constexpr uint8_t regs16Count = 2;
     static_assert(regs16Count > 0); // code is not ready for empty lists of registers
-    static const uint8_t regs16Addrs[regs16Count] PROGMEM;
+    static const Register regs16Addrs[regs16Count] PROGMEM;
     uint16_t regs16[regs16Count] = { 0, 0 };
 
     // 8bit init values to be sent to the MMU after line up
     static constexpr uint8_t initRegs8Count = 2;
     static_assert(initRegs8Count > 0); // code is not ready for empty lists of registers
-    static const uint8_t initRegs8Addrs[initRegs8Count] PROGMEM;
+    static const Register initRegs8Addrs[initRegs8Count] PROGMEM;
     uint8_t initRegs8[initRegs8Count];
 
     uint8_t regIndex;