Accelerometer - Failed to collect data, M955 parms ignored

kauedg

I have connected my accelerometer board successfully but can't get a reading from it.

RRF Version: 3.4.1
Boards: Duet2 Wifi, Duex5
Accelerometer: type LIS3DSH 16-bit resolution, SPI frequency 2000000

Configured it with

M955 P0 C"duex.cs6+spi.cs4" M955 P0

# Console:
M955 P0 C"duex.cs6+spi.cs4" M955 P0
Accelerometer 0 type LIS3DSH with orientation 6 samples at 1600Hz with 16-bit resolution, SPI frequency 2000000

Issue #1: Can't get readings from accelerometer
Connected the CS with a separate wire to duex.cs6 to avoid interference. But when I tried testing it with:

G90 G1 X130 G1 X180 G4 S2 M956 P0 S1000 A0 G4 P10 G1 X130 F20000

The resulting CSV is written as:

Sample,X,Y,Z
Failed to collect data from accelerometer

Then I tried changing it's configuration to the recommended 10 bit resolution, 1344Hz sampling rate, which led me to the second issue...

Issue #2: The M955 R and S parameters are ignored

M955 P0 C"duex.cs6+spi.cs4" I06 S1344 R10 M955 P0

# Console:
# Ignores the S and R new settings
M955 P0 C"duex.cs6+spi.cs4" I06 S1344 R10 M955 P0
Accelerometer 0 type LIS3DSH with orientation 6 samples at 1600Hz with 16-bit resolution, SPI frequency 2000000

Then I tried changing the Q parameter and it's accepted:

M955 P0 C"duex.cs6+spi.cs4" I06 S1344 Q1000000 M955 P0

# Console:
M955 P0 C"duex.cs6+spi.cs4" I06 S1344 Q1000000 M955 P0
Accelerometer 0 type LIS3DSH with orientation 6 samples at 1600Hz with 16-bit resolution, SPI frequency 1000000

I've already checked every connector for signal continuity and every pin source/destination twice. The cable 2m long sleeve with 10 cables in it.

Phaedrux

Can you test with a much shorter cable?

kauedg

@phaedrux I'll try that but the current cable length is just long enough for operation. I'll test with a cat5e ethernet cable.

dc42

Re issue 1, if the accelerometer is detected but doesn't collect data, the problem may be with the INT wire from the accelerometer to the Duet.

Re issue 2, the LIS3DSH doesn't support 1344Hz and it always returns 16-bit data. So the firmware is giving you the closest available configuration to the one you requested. The LIS3DH does support 1344Hz at reduced resolution.

kauedg

Replaced the sleeve cable with a cat5e ethernet one and now it works.

Graph is all over the place but it works.