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Readback of a signal with length 0 (VHDL2008)

See original GitHub issue

When I read back a signal of length 0, the conversion fails. I attached a minimal example. If the cntrlwidth is set to >0 it works. Signals with length 0 can for example be assigned to unused signals in buses. I expected the conversion to return 0.

Traceback (most recent call last):
#            File "binaryvalue_bug/binaryvaluetest.py", line 49, in test_cntrl
#            assert dut.Cntrl_in.value.integer == dut.Cntrl_out.value.integer
#            File "cocotb/cocotb/binary.py", line 294, in integer
#            return self._convert_from[self.binaryRepresentation](self._str)
#            File "cocotb/cocotb/binary.py", line 200, in _convert_from_unsigned
#            return int(resolve(x), 2)
#            ValueError: invalid literal for int() with base 2: ''

binaryValue.zip

Running on ModelSim DE version 2020.4 2020.10 (32bit) Running tests with cocotb v1.5.0.dev0 OS: CentOS 64bit

Issue Analytics

State:
Created 3 years ago
Comments:12 (12 by maintainers)

Top GitHub Comments

1reaction

ktbarrettcommented, Dec 16, 2020

Well as long as it’s consistent I guess I’m okay with it too. @Botnic @alexforencich Could one of you make the changes with a test for this case?

0reactions

eric-wiesercommented, Feb 23, 2021

How would you even write a null array with cocotb? Array writing is filled through python iteration, isn’t it?

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