InexactError while using the PiGPIO.jl package from JuliaBerry

New to Julia
1

Hi,

I am trying to read sensor (MPU 6050) data using Raspberry Pi 3 and Julia using the PiGPIO package. I have connected my Pi to the pigpio daemon over a network.

When I am trying to use “i2c_write_byte” function something like i2c_write_byte(pi, 2, 0x19), I end up with the following error:

InexactError: check_top_bit(UInt32, 4294967271)

Stacktrace:
[1] throw_inexacterror(::Symbol, ::Any, ::UInt32) at ./boot.jl:567
[2] check_top_bit at ./boot.jl:581 [inlined]
[3] toInt32 at ./boot.jl:630 [inlined]
[4] Type at ./boot.jl:716 [inlined]
[5] convert at ./number.jl:7 [inlined]
[6] _u2i(::UInt32) at /home/pi/.julia/packages/PiGPIO/e5h1O/src/pi.jl:72
[7] i2c_write_byte(::Pi, ::Int32, ::UInt8) at /home/pi/.julia/packages/PiGPIO/e5h1O/src/i2c.jl:99
[8] top-level scope at In[51]:1

I tried to look up the function in the boot.jl file in the line mentioned but wasn’t able to figure it out since I am new to coding. Could someone please explain what the actual error is and also how to rectify it if possible?

Thank you

2

It comes from the function at
https://github.com/JuliaBerry/PiGPIO.jl/blob/d3c8a4dd3a41548378f7054c85fec0ad00107e26/src/pi.jl#L71-L79

The function doesn’t really make sense to me, converting an unsigned integer to an Int32 can never give a negative result which is what is being checked.

I am guessing that instead of v = convert(Int32, x), what was intended was x % Int32.

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