SPI not working in BeagleBone Black #344
Comments
The version.sh is |
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Thanks for reporting, I will try to reproduce and investigate |
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Hi everyone. Any update on this issue? I am facing the same problem: SPI is not working in BeagleBone Black. I have followed this to properly setup the SPI pins, but using print(spi.xfer2([32, 11, 110, 22, 220])) gives me values [255,255,255,255,255] Thank you very much, The version.sh is: |
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The version.sh is git:/opt/scripts/:[b39ec679648a6be8f25f48bd1c9784c1fc5a0c46] |
No updates what so ever... I dropped working on it as there is so many differences in the documentation. |
Ok, Thanks. Could you recommend another library? Did you find a similar one, for Python or C++? Thanks in advance, Regards. |
i'm afraid cant. like i said i dropped working on it because of the lack of support and documentation |
Hi caxefaizan, I just wanted to tell you that although print(spi.xfer2([32, 11, 110, 22, 220])) gives me values [255,255,255,255,255], the SPI interface is apparently working well. I tried sending data using spi.writebytes([0x61]) and analyzing the outgoing signals (CLK, CS, D0, and D1) in the oscilloscope to see what I got. I have attached a picture with the transmission in action on the oscilloscope (blue-> chip select signal, green -> clock signal, pink-> data sent (0x61), yellow -> received data, Best regards, Dayrene |
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I'm testing with the Buster IoT Image 2021-01-11 image: Run #!/bin/bash
echo set SPI0 pins
config-pin p9.17 spi_cs
config-pin p9.21 spi
config-pin p9.18 spi
config-pin p9.22 spi_sclk
echo set SPI1 pins
config-pin p9.20 spi_cs
config-pin p9.28 spi_cs
config-pin p9.19 spi_cs
config-pin p9.42 spi_cs
config-pin p9.29 spi
config-pin p9.30 spi
config-pin p9.31 spi_sclkHere are the spidev device files that exist: I run debian@beaglebone:~$ cat test_spi.py
from Adafruit_BBIO.SPI import SPI
#spi = SPI(bus, device) #/dev/spidev<bus>.<device>
# /dev/spidev0.0
spi = SPI(0,0)
print(spi.xfer2([32, 11, 110, 22, 220]))
spi.close()
# /dev/spidev0.1
spi = SPI(0,1)
print(spi.xfer2([32, 11, 110, 22, 220]))
spi.close()
# /dev/spidev1.0
spi = SPI(1,0)
print(spi.xfer2([32, 11, 110, 22, 220]))
spi.close()
# /dev/spidev1.1
spi = SPI(1,1)
print(spi.xfer2([32, 11, 110, 22, 220]))
spi.close() The output: so this does seem to indicate a problem as this is supposed to be a loopback test. I'll investigate further. |
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It seems the issue may not be with Adafruit_BBIO. Here is a loopback test with the generic python spidev module which incorrectly reads I get the same seemingly incorrect results for the spidev test from Derek Molloy's book: @jadonk @RobertCNelson have you noticed any spi problems on newer images? For reference: |
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I've talked to @RobertCNelson and it looks like there might have been a regression in SPI since the last official image release (AM3358 Debian 10.3 2020-04-06 4GB SD IoT). It's possible the issue could have occurred between 4.14 and 4.19 kernel. |
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Update: I've been advised by @RobertCNelson to try earlier 4.19 kernel builds going back to the April 2020 build. They are all in our debian repo so it is matter of apt-get and then rebooting and retesting. I'll update when I am able to complete that progress. An alternative solution is to move ahead to the 5.8 kernel build in the beagle repo via apt-get. It has been confirmed by @MarkAYoder that SPI is working ok with that kernel. |
Hi. i am using BBB to get values in SPI mode but am not able to find a proper documentation to make it work. I have connected the pins for SPI0 with the Ic from which i want to get the values.
so my code includes
from Adafruit_BBIO.SPI import SPIthen i initialize the spi as
spi = SPI(1,0)followed by
spi.open(1,0)spi.writebytes([address])since it was not working i tried the tutorial on github.
but using
print(spi.xfer2([32, 11, 110, 22, 220]))gives me values[0,0,0,0,0]also doesnt seem to work.i used
config-pinto setup SPI pins and also tried editing theuEnv.txt toincludespidev1.0The text was updated successfully, but these errors were encountered: