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roondar · 21 July 2021, 22:58

One possibility is the DMACON value.
You set it to

Code:

move.w		#SETCLR|COPEN|BPLEN,DMACON(a2)

But this is not correct, you need to set the DMAEN bit (bit 9) as well.
Edit: I know this sounds like an odd thing, but DMAEN does not do what you might think if you read the HRM description. The HRM description suggests it activates all the DMA channels in bits 0-8. Instead, it merely makes it so that you can enable the DMA in those bits.

21 July 2021, 22:58	#7
roondar Registered User Join Date: Jul 2015 Location: The Netherlands Posts: 3,415	One possibility is the DMACON value. You set it to Code: move.w #SETCLR\|COPEN\|BPLEN,DMACON(a2) But this is not correct, you need to set the DMAEN bit (bit 9) as well. Edit: I know this sounds like an odd thing, but DMAEN does not do what you might think if you read the HRM description. The HRM description suggests it activates all the DMA channels in bits 0-8. Instead, it merely makes it so that you can enable the DMA in those bits. Last edited by roondar; 21 July 2021 at 23:12.