zxnDMA (sim)

[maziac]

This release includes an implementation of the zxnDMA for the internal simulator (zsim).
Please enable it in the "zsim" section like this:

 "zsim": {
               ...
                "zxnDMA": true,
               ...
            },

Explanation:
"zxnDMA": true/false. Defaults to false. If enabled the zxnDMA is available at port $xx6B. All internal register can be viewed:

What just has been changed is highlighted in red.
At the bottom you can see the last DMA copy operation.

Notes:
- when DMA is active it uses t-states. I.e. while CPU stepping the DMA operation is executed just before the next CPU instructions.
So, if you see a higher t-state number than expected it is probably because of a DMA activity in the background.
- The zxnDMA supports all modes: continuous, burst and also the prescalar.
- The DMA activity (setting of the registers) is additionally logged into the "OUTPUT" tab of vscode.
You can activate it by selecting "DeZog zsim: Hardware".

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This discussion was created from the release zxnDMA (sim).