diff --git a/IDE_Board_Manager/package_prusa3d_index.json b/IDE_Board_Manager/package_prusa3d_index.json
index 1a90fdc..fc31889 100644
--- a/IDE_Board_Manager/package_prusa3d_index.json
+++ b/IDE_Board_Manager/package_prusa3d_index.json
@@ -9,6 +9,28 @@
         "online": "https://github.com/prusa3d/Arduino_Boards"
       },
       "platforms": [
+        {
+          "name": "Prusa Research AVR Boards",
+          "architecture": "avr",
+          "version": "1.0.3",
+          "category": "Contributed",
+          "url": "https://raw.githubusercontent.com/prusa3d/Arduino_Boards/master/IDE_Board_Manager/prusa3dboards-1.0.3.tar.bz2",
+          "archiveFileName": "prusa3dboards-1.0.3.tar.bz2",
+          "checksum": "SHA-256:4c4acc8c0864727b3c196b7b028f8f3102da736f1bd706bb75736b61dd2f338e",
+          "size": "101213",
+          "help": {
+            "online": "https://github.com/prusa3d/Arduino_Boards/blob/master/IDE_Board_Manager/prusa3dboards-1.0.3.md"
+          },
+          "boards": [
+            {
+              "name": "Original Prusa i3 MK3 Multi Material 2.0 upgrade"
+            },
+            {
+              "name": "Original Prusa i3 MK3/MK3S Einsy RAMBo"
+            }
+          ],
+          "toolsDependencies": []
+        },
         {
           "name": "Prusa Research AVR Boards",
           "architecture": "avr",
diff --git a/IDE_Board_Manager/prusa3dboards-1.0.3.md b/IDE_Board_Manager/prusa3dboards-1.0.3.md
new file mode 100644
index 0000000..356bb78
--- /dev/null
+++ b/IDE_Board_Manager/prusa3dboards-1.0.3.md
@@ -0,0 +1,120 @@
+# Prusa Research Boards definition version 1.0.3
+
+## Boards supported
+- [Prusa MM control board](https://github.com/prusa3d/MM-control-2.0) using prusa3dboards-1.0.2.tar.bz2
+  - including bootloader
+- Einsy/miniRAMBo boards using prusa3dboards-1.0.3.tar.bz2
+  - including bootloader
+  - [Einsys](https://reprap.org/wiki/EinsyRambo)
+  - [miniRAMbo](https://reprap.org/wiki/MiniRambo)
+## Specials/Limits
+- Restricted cores version for the Einsy/miniRAMBo boards
+
+## Changes to previous version
+- Commented out `static unsigned char timer0_fract = 0;` in `/prusa3dboards/cores/wiring.c` 
+
+Folder Structure:
+
+    .
+    └── prusa3dboards
+        ├── bootloaders
+        │   ├── prusa_einsy_rambo
+        │   └── prusa_mm_control
+        ├── cores
+        │   └── prusa_einsy_rambo
+        ├── patches
+        ├── tools
+        └── variants
+            ├── prusa_einsy_rambo
+            └── prusa_mm_control
+
+File Structure:
+
+    .
+    ├── Prepare-new-version.sh
+    ├── package_prusa3d_index.json
+    ├── prusa3dboards
+    │   ├── avrdude.conf
+    │   ├── avrdude.md
+    │   ├── boards.txt
+    │   ├── bootloaders
+    │   │   ├── prusa_einsy_rambo
+    │   │   │   ├── License.txt
+    │   │   │   ├── Makefile
+    │   │   │   ├── avr_cpunames.h
+    │   │   │   ├── avrinterruptnames.h
+    │   │   │   ├── command.h
+    │   │   │   ├── lcd.c
+    │   │   │   ├── lcd.h
+    │   │   │   ├── settings.h
+    │   │   │   ├── stk500boot.c
+    │   │   │   ├── stk500boot.h
+    │   │   │   ├── stk500boot.hex
+    │   │   │   └── stk500boot_v2_mega2560.hex
+    │   │   └── prusa_mm_control
+    │   │       ├── Caterina-prusa_mm_control.hex
+    │   │       ├── Readme.txt
+    │   │       ├── build.txt
+    │   │       └── program.txt
+    │   ├── cores
+    │   │   └── prusa_einsy_rambo
+    │   │       ├── Arduino.h
+    │   │       ├── CDC.cpp
+    │   │       ├── Client.h
+    │   │       ├── HardwareSerial.cpp
+    │   │       ├── HardwareSerial.h
+    │   │       ├── HardwareSerial0.cpp
+    │   │       ├── HardwareSerial1.cpp
+    │   │       ├── HardwareSerial2.cpp
+    │   │       ├── HardwareSerial3.cpp
+    │   │       ├── HardwareSerial_private.h
+    │   │       ├── IPAddress.cpp
+    │   │       ├── IPAddress.h
+    │   │       ├── PluggableUSB.cpp
+    │   │       ├── PluggableUSB.h
+    │   │       ├── Print.cpp
+    │   │       ├── Print.h
+    │   │       ├── Printable.h
+    │   │       ├── Server.h
+    │   │       ├── Stream.cpp
+    │   │       ├── Stream.h
+    │   │       ├── Tone.cpp
+    │   │       ├── USBAPI.h
+    │   │       ├── USBCore.cpp
+    │   │       ├── USBCore.h
+    │   │       ├── USBDesc.h
+    │   │       ├── Udp.h
+    │   │       ├── WCharacter.h
+    │   │       ├── WInterrupts.c
+    │   │       ├── WMath.cpp
+    │   │       ├── WString.cpp
+    │   │       ├── WString.h
+    │   │       ├── abi.cpp
+    │   │       ├── binary.h
+    │   │       ├── hooks.c
+    │   │       ├── main.cpp
+    │   │       ├── new.cpp
+    │   │       ├── new.h
+    │   │       ├── wiring.c
+    │   │       ├── wiring_analog.c
+    │   │       ├── wiring_digital.c
+    │   │       ├── wiring_private.h
+    │   │       ├── wiring_pulse.S
+    │   │       ├── wiring_pulse.c
+    │   │       └── wiring_shift.c
+    │   ├── patches
+    │   ├── platform.txt
+    │   ├── tools
+    │   └── variants
+    │       ├── prusa_einsy_rambo
+    │       │   └── pins_arduino.h
+    │       └── prusa_mm_control
+    │           └── pins_arduino.h
+    ├── prusa3dboards-1.0.0.md
+    ├── prusa3dboards-1.0.0.tar.bz2
+    ├── prusa3dboards-1.0.1.md
+    ├── prusa3dboards-1.0.1.tar.bz2
+    ├── prusa3dboards-1.0.2.tar.bz2
+    ├── prusa3dboards.version
+    ├── prusa3drambo-1.0.0.tar.bz2
+    └── prusa3drambo-1.0.1.tar.bz2
\ No newline at end of file
diff --git a/IDE_Board_Manager/prusa3dboards-1.0.3.tar.bz2 b/IDE_Board_Manager/prusa3dboards-1.0.3.tar.bz2
new file mode 100644
index 0000000..43d96f3
Binary files /dev/null and b/IDE_Board_Manager/prusa3dboards-1.0.3.tar.bz2 differ
diff --git a/IDE_Board_Manager/prusa3dboards.version b/IDE_Board_Manager/prusa3dboards.version
index 521fbad..222aba4 100644
--- a/IDE_Board_Manager/prusa3dboards.version
+++ b/IDE_Board_Manager/prusa3dboards.version
@@ -1,3 +1,4 @@
+1.0.3   # Fix "timer0_fract = 0;" warning
 1.0.2   # With bootloader and compiler.c.elf.extra_flags for Prusa Einsy/RAMBo Prusa Frimware
 1.0.1   # Added Einsy/miniRAMBo boards
 1.0.0   # Original Prusa i3 MK3 Multi Material 2.0 upgrade
diff --git a/IDE_Board_Manager/prusa3dboards/cores/prusa_einsy_rambo/wiring.c b/IDE_Board_Manager/prusa3dboards/cores/prusa_einsy_rambo/wiring.c
index 82bb518..22c9e68 100644
--- a/IDE_Board_Manager/prusa3dboards/cores/prusa_einsy_rambo/wiring.c
+++ b/IDE_Board_Manager/prusa3dboards/cores/prusa_einsy_rambo/wiring.c
@@ -37,7 +37,7 @@
 
 volatile unsigned long timer0_overflow_count = 0;
 volatile unsigned long timer0_millis = 0;
-static unsigned char timer0_fract = 0;
+//static unsigned char timer0_fract = 0;
 
 // As of Prusa Firmware 3.8 we need to disable the Arduino's hardcoded TIMER0_OVF_vect
 // to be able to replace it with our own implementation for HW PWM heatbed control.