# Firmware upload issue
**URL:** https://forums.maslowcnc.com/t/firmware-upload-issue/15900
**Category:** Software
**Tags:** firmware
**Created:** [January 23, 2021, 3:59pm UTC](https://forums.maslowcnc.com/t/firmware-upload-issue/15900 "2021-01-23T15:59:25Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@Fiber.studios.co](https://forums.maslowcnc.com/u/Fiber.studios.co)
#### Post date: [January 23, 2021, 3:59pm UTC](https://forums.maslowcnc.com/t/firmware-upload-issue/15900/1 "2021-01-23T15:59:25Z")
recently purchased the m2. we are trying to update the firmware. we had to install the duo board on our IDE. then we chose the programming port. and uploaded 1.26 of the firmware. we received error message : avr/io .h. we have tried various combinations of ports and boards, double checked the file was unzipped.
forums told us that the firmware may come pre loaded. but we are having trouble getting any sketch uploaded. when we try and do a hard reset of the board we get error message below:
:Arduino: 1.8.13 (Mac OS X), Board: “Arduino Due (Programming Port)”
In file included from sketch/Maslow.h:40:0,
from sketch/Axis.cpp:19:
RingBuffer.h:21:11: error: redefinition of ‘class RingBuffer’
class RingBuffer{
^
In file included from /Users/mudafuckinbizznasty/Library/Arduino15/packages/arduino/hardware/sam/1.6.12/cores/arduino/UARTClass.h:23:0,
from /Users/mudafuckinbizznasty/Library/Arduino15/packages/arduino/hardware/sam/1.6.12/variants/arduino\_due\_x/variant.h:38,
from /Users/mudafuckinbizznasty/Library/Arduino15/packages/arduino/hardware/sam/1.6.12/cores/arduino/Arduino.h:201,
from sketch/Maslow.h:26,
from sketch/Axis.cpp:19:
RingBuffer.h:30:7: error: previous definition of ‘class RingBuffer’
class RingBuffer
^
In file included from sketch/Maslow.h:40:0,
from sketch/GCode.cpp:21:
RingBuffer.h:21:11: error: redefinition of ‘class RingBuffer’
class RingBuffer{
^
In file included from /Users/mudafuckinbizznasty/Library/Arduino15/packages/arduino/hardware/sam/1.6.12/cores/arduino/UARTClass.h:23:0,
from /Users/mudafuckinbizznasty/Library/Arduino15/packages/arduino/hardware/sam/1.6.12/variants/arduino\_due\_x/variant.h:38,
from /Users/mudafuckinbizznasty/Library/Arduino15/packages/arduino/hardware/sam/1.6.12/cores/arduino/Arduino.h:201,
from sketch/Maslow.h:26,
from sketch/GCode.cpp:21:
RingBuffer.h:30:7: error: previous definition of ‘class RingBuffer’
class RingBuffer
^
sketch/GCode.cpp: In function ‘void initGCode()’:
GCode.cpp:32:21: error: ‘class RingBuffer’ has no member named ‘empty’
incSerialBuffer.empty();
^
sketch/GCode.cpp: In function ‘void readSerialCommands()’:
GCode.cpp:64:54: error: ‘class RingBuffer’ has no member named ‘write’
int bufferOverflow = incSerialBuffer.write©; //gets one byte from serial buffer, writes it to the internal ring buffer
^
In file included from sketch/Maslow.h:40:0,
from sketch/Motion.cpp:17:
RingBuffer.h:21:11: error: redefinition of ‘class RingBuffer’
class RingBuffer{
^
etc…
Please Help. what are we missing? anything would be helpful!
Thank you.
---
### Author:  [@bar](https://forums.maslowcnc.com/u/bar)
#### Post date: [January 23, 2021, 5:17pm UTC](https://forums.maslowcnc.com/t/firmware-upload-issue/15900/2 "2021-01-23T17:17:31Z")
@makermade do you guys have any thoughts? This is beyond my understanding of that machine.
---
### Author:  [@Fiber.studios.co](https://forums.maslowcnc.com/u/Fiber.studios.co)
#### Post date: [January 23, 2021, 6:04pm UTC](https://forums.maslowcnc.com/t/firmware-upload-issue/15900/3 "2021-01-23T18:04:24Z")
We have now successfully reset the board. in an effort to start from scratch. when trying to upload the firmware we now get error message : redefinition of ‘class Ringbuffer’
thanks again for any help. @MakerMadeCNC
---
### Author:  [@Orob](https://forums.maslowcnc.com/u/Orob)
#### Post date: [January 23, 2021, 7:49pm UTC](https://forums.maslowcnc.com/t/firmware-upload-issue/15900/4 "2021-01-23T19:49:17Z")
Version 1.26 is for the mega. it won’t work. You have a due. Try this [version](https://github.com/makermadecnc/maslowdue).
---
### Author:  [@Patrick](https://forums.maslowcnc.com/u/Patrick)
#### Post date: [January 25, 2021, 4:29pm UTC](https://forums.maslowcnc.com/t/firmware-upload-issue/15900/5 "2021-01-25T16:29:11Z")
This is the correct link, thanks for sharing. @Fiber.studios.co if you still have trouble, you can send a note to [support@makermade.com](mailto:support@makermade.com) requesting additional instructions for firmware update