cpu/ns32000: add NS32CG16 graphics/printer variant#15569
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Adds the NS32CG16, an NS32016 plus the Series 32000 graphics instructions (Format-5 extensions): the bit-string ops (MOVMP, BITWT, TBITS, SBITS, SBITPS), the BitBlt instructions (BBOR, BBXOR, BBAND, BBFOR, BBSTOD), and EXTBLT. EXTBLT drives an optional DP8510/DP8511 BITBLT processing unit via set_bpu(), and degrades to a pseudo-DMA source-to-destination copy when none is connected. Disassembler support for the new Format-5 opcodes is included, and instruction timing follows the published NS32CG16 (B-stepping) data. emax2 (Emax II) is switched from a placeholder NS32016 to the NS32CG16.
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As usual, there is additional information, including the CG16 Programmers Reference, at [https://github.com/davidlrand/mame-system-media/tree/main/NS32CG16] including the emulation library, additional application notes, and the WordStar (!) source files for many of them. |
pmackinlay
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Jun 22, 2026
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Looks good except the tight coupling to BPU.
Drop the direct dependency on the concrete DP8510 device: remove the video/dp8510.h include, the optional_device<dp8510_device>, set_bpu() and the bpu() accessor. EXTBLT now runs the plain source-read / destination-read / write bus cycles and asserts a new out_bpu() write line for the duration of the transfer. A DP8510 attached in the driver snoops those cycles via memory taps, latching the source/destination words and substituting its processed output on the write. With no BPU connected the cycles run as a plain source-to-destination copy.
pmackinlay
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Jun 23, 2026
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Only one more request, thanks for your patience.
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| protected: | ||
| virtual dp8510_device *bpu() const override; | ||
| virtual void bpu_window(bool active) override { m_out_bpu(active); } |
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Please make this output active low (active==0) to match the hardware.
The NS32CG16's /BPU window strobe is active low; emit the physical level (0 = low/asserted) rather than the logical active flag.
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Adds the NS32CG16, an NS32016 plus the Series 32000 graphics instructions
(Format-5 extensions): the bit-string ops (MOVMP, BITWT, TBITS, SBITS, SBITPS),
the BitBlt instructions (BBOR, BBXOR, BBAND, BBFOR, BBSTOD), and EXTBLT. EXTBLT
drives an optional DP8510/DP8511 BITBLT processing unit via
set_bpu(), anddegrades to a pseudo-DMA source-to-destination copy when none is connected.
Disassembler support for the new Format-5 opcodes is included, and instruction
timing follows the published NS32CG16 (B-stepping) data.
emax2 (Emax II) is switched from a placeholder NS32016 to the NS32CG16.