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Hi all,
I have recently finished building a Rostock Max V2 however have run into a problem. The build was fine and I successfully uploaded the Repetier firmware and the LCD screen is functioning as indicated in the manual (displaying sensible nozzle and bed temperatures, and default 100% speed and flow). I then installed mattercontrol and successfully connected to the printer however, at this point things went a bit awry.
Firstly, I noticed the temperature display in the software was showing 0C for the nozzle and the bed and just stayed there, despite the LCD screen displaying approx 20C.
I moved onto the basic functional checks and when I opened the terminal I found that there was an accelerometer i2c send/receive error and an SD card initialisation error (shown below).

-start
->Communication State: Connected

<-
->M115

<-Transformation matrix: 1.000000 0.000000 0.000000 0.000000 1.000000 0.000000 0.000000 0.000000 1.000000
<-
<-Free RAM:879
<-
<-Autoretract:0
<-
<-X:0.00 Y:0.00 Z:0.000 E:0.0000
<-
<-SpeedMultiply:100
<-
<-SD init fail
<-
<-iis2dh accelerometer initializing...
<-
<-accelerometer send i2c error.
<-
<-accelerometer i2c recv error.
<-
<-accelerometer send i2c error.
<-
<-accelerometer i2c recv error.

etc...

This prevented me from proceeding with the functionality checks but I thought I'd check to see if I could manually move the axes and I found that I could (although there was a approx a 5 second delay after I clicked the move axis button in the software and sometimes I had to double click and sometimes it just didn't move at all).

I then tried to command a nozzle and bed temperature but this didn't work and the temp just stayed where it was and showed 0 in the software (also the heated bed LED did not come on).

After this I decided to recheck all the wiring - everything was correct and I was getting 12.2V at the powersupply connector (I only checked voltage in). Then it got weird, without changing anything I still had the accelerometer error like before but all of a sudden the temperature was showing up in the software and I was able to manipulate the temp of the bed and the nozzle. However this was short lived and after only for a few minutes it fell to 0 again. Also at one point the LCD screen showed rows of black squares for a couple of seconds then returned to the normal screen.

Does anyone have any thoughts on what could be the issue here? Am I right in thinking that if there is an i2c send/receive error this could be something physically wrong with the accelerometer or processor (as this protocol is only used between peripheral ICs and processors right?) or could it be configuration related? I'm new to this game so I'd really appreciate any advice

Also, not sure if it's relevant but I'm running Windows 10, repetier 0.92.2 and matter control 1.5

The simple answer is this:

The accelormeter is erroring because it isn't present. That's something on the Eris. See if you haven't missed defining the printer as 2, and the motherboard as 301 real quick.

Hi Xenocrates,

Thanks for the response. I actually spoke to support and they ended up telling me the same thing, I don't actually have an accelerometer on the Rambo board, hence the communication error. They said that this error message, however, would not affect performance. But surely there is a way to reconfigure this. Can I just disable the probing function somewhere in the firmware so this message does not pop up? It seems as if everyone with a Rostock Max would have this issue? Doesn't seem right...
Also I did check the config in the firmware, I have printer 2 and motherboard 301.

You could comment out the line in the firmware which instructs the printer to send the error message...

You have simply to change the minimum temperature on line 59. by default temp are 17.
// ################ END MANUAL SETTINGS ##########################

#define MIN_DEFECT_TEMPERATURE 12 // this is the min temp that will allow the hotend to start heating. Below this it will show as defective to help identify bad thermistors
#define MAX_DEFECT_TEMPERATURE 300 // this is the max temp that wthe printer will throw errors about defective thermistors

I personally think you may have uncovered a bug in the latest V2 code. Until late last year the V2 did not have a Z probe feature and all worked fine. Even with it enabled as the default was. However there have been changes to the firmware to integrate the accelerometer probe and maybe it has no longer been tested on a machine without an accelerometer.

Anyway you can disable it in the firmware in configuration.h line 666 #define FEATURE_Z_PROBE 1. Change the 1 at the end of the line to a zero. Hope the works as I can not test it since I now have upgraded to the HE280 hot end.

Dale