GRC Hier block with vector IO not working as expected

Hi list,

I’m currently in the process of porting my gr-drm project to the 3.7 API
and now I’m a little bit stuck and hope that someone here can help me.

I want to create a hier block (in GRC) that accepts vectors as input and
output. Their size is controlled by parameters like vlen_in and
vlen_out.
Unfortunately, the IO size of the generated hier block always stays 1,
no
matter what I use as parameter. I attached a minimal (pure GNU Radio)
example flow graph and hier block that reproduces my problem. Maybe I
overlooked something obvious, but I don’t get why this is not working.

If someone had the time to try this and could report if it works (it
does
not for me), I would be very grateful.

I’m on Ubuntu 12.10 and have GNU Radio v3.7.2.1-116-ge751e54a installed.

Regards,
Felix W.

Hi Felix,

I can reproduce it. Problem is that the generated ‘xml’ file is not
generated correctly. The parameter ‘vlen’ should be written as ‘$vlen’
in
the xml files source/sink section but it is written as ‘vlen’. Thus
‘vlen’
is treated as the value. Happens with ‘v3.7.2-11-g3b27cc47’. I don’t
know
how to fix it though.

Happy hacking
Johannes