Have been trying to write a block in Python. Did not use the modtool.py, since my understanding is it may not yet support that.
The block has only one output, no inputs. Also wrote the corresponding XML file. the
block shows up correctly in GRC when I select it and add it to the flowgraph.
I've defined the output signature in the work function ( 1, 1, gr.sizeof_float). My work function writes to output_items[0][ some indexes] and returns with a count of the number of written output items.
Initially I derived the block from gr.block, but it complained about no connection to the output, so I changed it to derive from gr.hier_block2. When running the flowgraph with my block in it, gnuradio complains that there is no output connection inside my block.
The question is 'what' internally connects my output_items to the block's output?
I tried self.connect(myblockname, (self, 0)) to satisfy the connection, but myblockname apparently needs some sort of modifier in order to be a valid output that can be connected to the block's output. Tried looking through python blocks in the source, and the 3.7.2 API, but no luck so far...
Any advice?
-- Tom, N5EG