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- To: hatari-devel@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [hatari-devel] DSP Bootstrap ROM
- From: Andreas Grabher <andreas_g86@xxxxxxxxxx>
- Date: Fri, 24 Sep 2021 13:21:55 +0200
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> Am 24.09.2021 um 12:29 schrieb Thorsten Otto <admin@xxxxxxxxxxx>:
>
> On Freitag, 24. September 2021 08:26:18 CEST Thomas Huth wrote:
> > maybe leave it
> > disabled by default until we hit a program that really requires this.
>
> I cannot imagine how a program would need that. Its ROM afterall, and on real hardware you cannot change that behaviour.
>
I just noticed, that Hatari misses some of the bootstrap loop hack. Obviously I added that for Previous some years ago (dsp_core_write_host(), case CPU_HOST_ICR). The loop hack needs to stop, when host flag 0 (HF0) is set to 1. NeXTstep uses this function. There is also some DMA bits in the ICR, but it seems Atari did not use DSP DMA.
I agree that most parts of the bootstrap program might be not relevant. Some program might use the OMR to change mode, but I did not see one on the NeXT (but I did not test many DSP programs).