Contributor
Super ContributorDo you have a storage qualifier enabled? It doesn't look like it from your waveform, but it's the only thing I can think of as to why the trigger sample at 0 does not match your trigger condition.
Have you tried a comparison trigger instead of this complicated advanced trigger? Choose comparison instead of advanced for the trigger condition column. You can set a range of values for the address bus to trigger on, like what you have here. But again it doesn't explain what you're seeing.
I presume you're using a mnemonic for sr_A that's named ADDRESS since sr_A doesn't appear in your trigger condition.
Is the DATA qualification of 0202h necessary?
Just throwing stuff out here to look at.
Contributor@sstrell just to answer your questions:
1) No storage qualifier
2) Comparison trigger - no - I need to avoid recompilation (which takes ages) when I'm trying to debug so I have the complicated advanced trigger in place that I can tweak at runtime
3) Yes, ADDRESS is an alias for sr_A
4) Data comparison for 0202h was necessary as I was trying to work out what is writing this data when it shouldn't be
Just some background - I have 2 8bit SRAM chips sharing the same address lines so that I can store 16 bits of data with the same address. When I was writing to 140h, I found that 4140h also contains the same data - so I've been trying to work out why. Seemed like a problem with address line 14 (the 4xxxh) but I still haven't worked it out yet. Time is short when it comes to my hobby, so apologies in the time it took to respond to your questions.
I haven't figured it out yet but I will keep investigating when I can. I don't think it's related to my FPGA code. I have 2 identical chips so I'm going to try a similar exercise with an Arduino and then repeat with the chips I'm using now.
