Endstops pullup resistors always low

Hello everyone,

Am having some problems with my sanguino. The endstops don't seem to work they stay in the low configuration. First I thought I might have blown up the ATmega so I ordered another one. Much to me surprise this one had the exact same issue.

So what have I tried so far:

Clean sprinter firmware
measured if SIG is in anyway connected to GND (It isn't)
Bought a new ATmega 1284p
Clean merlin firmware
Bent microcontroller pin so it isn't connected to the board (still low)

I have some basic knowledge of electronics but not enough so solve this issue I hope there is someone that can help me out.

Edit:
The board works perfectly other then the endstops and the X axis going only one way. This isn't my first printboard I have soldered but a mistake is possible, even tough everything pretty much seems to work.

Edited 2 time(s). Last edit at 08/21/2013 09:34AM by Eddie4.

The endstop pullups on Sanguinololu aren't on the board. The AVR has switchable pullups on the I/O pins, which is why leaving the pin disconnected doesn't help.

In Marlin Configuration.h, you need to uncomment "#define ENDSTOPPULLUPS" to make this happen. Also make sure the correct board type is selected (62 if not using external fan control). Not sure about Sprinter.

> The endstop pullups on Sanguinololu aren't on the
> board. The AVR has switchable pullups on the I/O
> pins, which is why leaving the pin disconnected
> doesn't help.

I used #define ENDSTOPPULLUPS in both my configs so it should pullup when I leave the pin disconnected. And yes the board is set to 62

Edited 1 time(s). Last edit at 08/21/2013 12:39PM by Eddie4.

Seems that my fuse settings were off.

[reprap.org]



How i fixed my problem:
What you need to do is go into your arduino folder C:\Program Files (x86)\Arduino\hardware\Sanguino\ and edit the security of the file boards.txt to allow you're user to edit it. After that Edit the fallowing lines in the 644p section to:

atmega644.bootloader.low_fuses=0xFF
atmega644.bootloader.high_fuses=0xDC
atmega644.bootloader.extended_fuses=0xFD

Then reburn you're bootloader

I reflashed the firmware as well just to be sure