Xilinx/xup_vitis_network_example

Where is the definition of the "_start()" in the DataMover class?

Ossic opened this issue · 3 comments

Ossic commented

Hi, I would like to ask just one question for vnx_utils.py.
Where is the definition of the function _start() referred in the class DataMover of vnx_utils.py? Please note just one " _ " in front of the "start".
I assume that the function is defined in DefaultIP as the parent class in the overlay.py file. However, in pynq2.7, there are only _start_sw(...) and _start_ert(...) defined which seems to be some kind of connection.

Intriguingly, vnx-basic.ipynb does work completely.

Wishing you guys having a good day !

Run Time
Card: Alveo U50
OS version: Ubuntu 18.04.6 LTS/5.4.0-122-generic
pynq version: 2.7.0
Git branch: master
XRT Version: 2.11.634
XRT Branch: 2021.1

mariodruiz commented

Hi @Ossic,

You are right, there is a bug in the code. This driver is working because the start() method of the DefaultIP is being called.

Mario

Ossic commented

Hi @mariodruiz
Thanks for your reply! It still confuses me that what makes python interpreter bypass the "start()" function in DataMover class and thus makes the "start()" function in DefaultIP work priorly. Please forgive my poor grammar skills about python.

mariodruiz commented

I think the problem is that the .start method is assigned in the __init__ function of DefaultIP this could potentially skip the redefinition of the start method in the derived class.