Can a LIS3DH be installed on a duet 3mini 5+ ran from a duetPI?

RatRig0331

I have my LIS3DH wired up to my duet 3 mini 5+ Using the recommended io3 port for in/out and temp daughterboard port and every time I send a m955 p0 c”io3.out+io3.in” I always get a message accelerometer not found error

I checked all my wires with a meter to check my crimps and they all make good contacts from the LIS3DH chip to the motherboard plug ends

I don’t know if it makes a difference but I am running from a rasPi with duetPI

Diagnostics
Board: Duet 3 Mini 5+ (Mini5plus)
DSF Version: 3.4.0
Firmware: RepRapFirmware for Duet 3 Mini 5+ 3.3 (2021-06-15)

Phaedrux

It should be supported in SBC mode as well in 3.4

https://docs.duet3d.com/en/User_manual/Connecting_hardware/Sensors_Accelerometer

dc42

@ratrig0331 the most common reason for accelerometers not working with the Duet 3 Mini (other than wiring errors) is that the wire carrying the CS signal is picking up interference from one of the other wires.

RatRig0331

@dc42 I just rewired the run with shielded foil and bonded cable wire, all the connections are good and still the same results

dc42

@ratrig0331 please post photos of both ends of your wiring. How long is the cable?

chrishamm

@ratrig0331 You should use equal RRF and DSF versions so it's better to upgrade the firmware once using M997 before you continue. In order to get my LIS3DH working, I had to add a 1k resistor to the accelerometer end of SDO as well.

dc42

A small capacitor (100 to 500pF?) connected between the CS and ground pins of the LIS module might work too.

RatRig0331

@chrishamm

3/31/2022, 10:40:32 AM M997
Error: Operation has been cancelled

RatRig0331

@dc42 the cable run is 75inches long, I’ll take pics tonight and post them as soon as I figure out how to make them URL’s

dc42

@ratrig0331 the long cable is probably the problem. I only tested up to 1 metre.

You could try reducing the SPI data rate, for example to 1MHz by including Q1000000 in the M955 command.

RatRig0331

@dc42 I’ll give that a shot when I get home to at the “q” value, I can’t go much shorter than 75 inches my set up is a 500x500x500 xy core printer

gloomyandy

@ratrig0331 Some folks have reported using up to 3m connections when using a USB3.0 style cable. See: https://forum.duet3d.com/topic/22878/software-package-3-3beta3-released/57?_=1624809172098 This seemed to work well when other cables (like cat5) did not.

jay_s_uk

@ratrig0331 I run a 2.7m USB3 cable quite happily

RatRig0331

@dc42 tryed the m955 p0 c”io3.out+io3.in” q1000000 and same result I ordered a set of “pf” sizes100-10000 off Amazon for $7usd due in this Saturday so I will give that a try

RatRig0331

@dc42 my new multimeter can in today, my lines still show good connection from the duet to the chip I’m also getting the following on the chip side

G to vcc 3.296v
G to scl 1.815v
G to sda 3.296v
G to sdo 2.661v
G to cs 3.296v
G to int1 3.283v

RatRig0331

@dc42 looks like I was fighting a bad chip the first one was no good the second one I tryed was no good and than the third one lit it’s little beacon of the success led right off the bat and the duet found it, however is it normal if I send the m955 p0 c”io3.out+io3.in” over and over it will find it than the next it won’t, than once more it will find it than if I send it once mor it won’t