ADXL345 Not Working
hi! i got this error and the connection with the adxl its good
Invalid adxl345 id (got ca vs e5).
Invalid adxl345 id (got ca vs e5).
This is generally indicative of connection problems
(e.g. faulty wiring) or a faulty adxl345 chip.
56 Replies
The wiring of the sensor is critical - mine was weird using untwisted cables and it fails to connect 80% of the time
The longer the cable the more shielded cables or a tp network cable are recommended
@chrizzar recommended the following: Twisted pair order for three twisted pairs:
GND+MISO
3.3V+MOSI
SCLK+CS
Note that unlike a cable shield, GND must be connected at both ends.
I she yet to try this but I am confident
Cool cool, I hope it works out for you! 🙂
I used a Cat6 cable and for each twisted pair I used one for ground and the other for one of the connections. That made it a rock solid connection and I have never had a ADXL issue
Same
optimistic-goldOP•2y ago
okey. i will try with cat 6
i used cat 6 cable. didnt work
i will buy an new adxl to test
How did you wire it up to the cat6 cable?
optimistic-goldOP•2y ago
with dupont connectors
I also finished my cat6 based cable - as described above - can't get a connection either. I also think that I fried my ADXL...
did you take each twisted pair and use one of the wires for ground?
Pair 1 - Orange/White is 5V, Orange CS; Pair 2 - Green/White Ground, Green SDA; Pair 3 - Blue/White Ground, Blue SDO; Pair 4 - Brown/White Ground, Brown CLK.
absent-sapphire•2y ago
Hello, can you please explain a bit wider what need to be dote to cables ? As i understand i need to take usual LAN cat6 cable. Have pairs twisted together and then i will need to solder all 5 White wires to GDN contact on both ends ?
optimistic-goldOP•2y ago
will test taht
cat cable is able to transmit log distances because the ground is wrapped around the data lines. If you don't follow that then you will get cross talk, which the ADXL is extremely sensitive to
passive-yellow•2y ago
I had this same issue when I first installed it. I found those same instructions that blacksmith posted before. Worked like a charm. It's not all four white wires though. Read it again. The orange/white and orange pair do not have a GND connection.
absent-sapphire•2y ago
but the rest ( red, blue, yellow, green) should have GND ( white) soldered to gnd port on adxl and gnd connector to the board?
passive-yellow•2y ago
network cables only have four pairs. Three of those pairs will have the white/(color) connected to ground. The forth pair is used for +5 and CS. Blacksmith lays it out completely in his post. I'm not sure what kind of cable you are using, as network cables always use brown,green,blue and orange with a corresponding white with a a colored stripe.
I would also recommend soldering good silicone or PTFE wire and using a connector rated for moving parts (like jst-sm or molex). Then attach your CAT6 wire to the connector. the CAT6 wire will break eventually and you want to make it easy to replace it (unless you are good at desoldering. I am not, and it was a real pain to get it disconnected)
optimistic-goldOP•2y ago
the adxl was bad
but now i have another problem
optimistic-goldOP•2y ago
optimistic-goldOP•2y ago
optimistic-goldOP•2y ago
optimistic-goldOP•2y ago
optimistic-goldOP•2y ago
so i need to put together all grounds?
correct
optimistic-goldOP•2y ago
okey im on it
the ground cables can be not cat?
like connect that 3 grounds cables to an single cable and that connect to ground
I don't understand, I listed all the cables within the CAT cable and what to use them for
optimistic-goldOP•2y ago
i mean, i got 3 grounds cable in cat 5e cable
can i merge that cable with an single cable to fit duppont conector?
yeah as long as they are all connected eventually
optimistic-goldOP•2y ago
okay
I ran a very short length (like 7cm) of multistrain silicone lined wire to JST-SM connectors. That way I can easily replace the CAT cable in the future since its wiring doesn't seem to last as long as I would have hoped
optimistic-goldOP•2y ago
can i see that?
sorry I am at work right now and can't get a picture
optimistic-goldOP•2y ago
Okay!
optimistic-goldOP•2y ago
Like that @blacksmithforlife 🇺🇸
optimistic-goldOP•2y ago
With 3 grounds as 1
sorry it is a bit hard to see
optimistic-goldOP•2y ago
Wow I will do like this
But
At this moment look at this
optimistic-goldOP•2y ago
optimistic-goldOP•2y ago
That it’s the correct scheme @blacksmithforlife 🇺🇸
?
can't tell from the photo, just follow my post above for what wire goes where
optimistic-goldOP•2y ago
Yep it’s connected like the post
I’m going to test now
that brown wire looks suspect, is it fully seated?
optimistic-goldOP•2y ago
now its
but didnt work
optimistic-goldOP•2y ago
optimistic-goldOP•2y ago
and that acelerometter was working
i connected to 3.3v need to connect to 5v?
I prefer to connect to 5v. Those ADXL can handle the extra voltage and just gives you a bit more room for error
optimistic-goldOP•2y ago
okey im going to try
connected to 5v
rebooting
getting 4.95v with multimeter
but still not working
the adxl was working previusly with basic cable at 3.3v
all cables get continuity
scl 3.3v sda 0.02v sdo 0.33v
optimistic-goldOP•2y ago
optimistic-goldOP•2y ago
@blacksmithforlife 🇺🇸
not sure, I personally have not had good results when attaching via dupont connects like you have
optimistic-goldOP•2y ago
Okey will try DIRECT Connect
I Connected DIRECT to adxl but duppont on The mainboard
Still didnt work
U direct connect The mainboard too
@blacksmithforlife 🇺🇸
you saw my pictures earlier, for connecting to the mainboard I use a single big dupont connector. But I have had it be fiddly o n the dupont (which again is why I don't like them)
optimistic-goldOP•2y ago
Can i See The duppont at The mainboard
absent-sapphire•2y ago
Hello again. i've tried different cables. With a new one (special signal cable with heavy shielding) im getting ff vs e5 instead o vs e5. I've connected wires to the RPi , added in config file this lines :
[include RatOS/sensors/rpi-adxl345.cfg]
[include RatOS/boards/rpi/config.cfg]
and getting the error. Can't make ity working for 2 weeks already ( Any ideas?
absent-sapphire•2y ago
Thank you very much for the great solution, seems a lot of people have problems with this, and your wiring worked for me where nothing else would. Simple Cat5 multi-stranded cable and a run of around 1.5m from my printhead to my cb1 mb with manta m8p, and once wired in as per your instructions, rock solid. 👍