MB02 DMA Port

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Number $xx0B
Decimal 11
Short desc. Controls Z8410 DMA chip via MB02 standard.
Bit Mask ---- ---- 0000 1011
Readable No
Writable No
Subsystem DMA

since core 3.1.2 this port $0B is supported and always in "Zilog DMA" mode, for "zxnDMA" use Datagear DMA Port ($xx6B / 107).

Currently not supported by latest core 3.0.7 (unclear whether it was ever supported in some older 2.0 cores, or the support was just planned, but currently not working at all)

If you have DMA app expecting the port to be $0B, you have to patch it to use the new data-gear port $6B. Also keep in mind the zxnDMA is by default in zxnDMA mode, while all the regular MB-02 SW does expect Zilog-like functionality, so the Next has to be reconfigured first by bit 6 of Peripheral 2 Register ($06) before running the app.