Remember when I said this could be dangerous?
While waiting for my USB scope to arrive I thought I’d poke around the board a bit more with my woefully inadequate tool: the multimeter. Things didn’t go so well.
Read on.
Pay attention part 2.
There are 12 discrete items that sit on the main data bus which are now, in theory, properly hooked up to the propeller chip. The theory is clearly standing on shaky legs for, as we have discussed, there is just too much noise on the D0-D7 data lines which cannot be explained away if everything is actually properly hooked up.
Here then, we go on a walking tour of the data bus and discover that we really weren’t paying attention.
Read on!
What’s that?
Code!
:main_machine_loop ' Read Dedicated Switches (swlo) and outa, busmask ' turn off data bus or outa, SWLOmask ' set data bus to SWLO andn dira, d0tod7mask ' set D0-7 to be input mov SWLO, ina ' read D0-7 to temp and SWLO, d0tod7mask ' mask out Data bits mov temp1, PAR ' HUB address of data add temp1, #8 ' SWLO is +2 longs wrlong SWLO, temp1 ' write SWLO 32 bits to HUB
And there’s more where that came from. Read on.