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Yep, in the STM32F4 and STM32F7 series. I'm reading the manual of the STM32F7 right now. Not a separate processor like the PRU-ICSS in the TI chips, just fast single-ended I/Os. I am more comfortable with the FPGA approach though, since it will buy us a bit more speed and flexibility at...

The biggest advantage of the FPGA+ARM SoC chips is the speed of the interconnect between the FPGA and processor. Anything comparably fast with a separate FPGA and ARM SoC would require a lot of routing effort to get anywhere near as fast of an interface. I think I'm gonna retain the bus control...

I struggle with the feeling of inauthenticity it gives me, but the way I see it is that whatever processor I use is going to run at a clock at least 3x higher than any of these FPGA cores and dispatch as many as two instructions per cycle. So there is a penalty to be paid in terms of the...

Yeah, I should ditch the Snapdragon entirely for 68000 systems. On these, I am eyeing the (not yet in production) STMicroelectronics STM32H7, which is related to the STM32F4 that bbraun was using. The STM32H7 is a 400 MHz ARM Cortex-M7, basically the fastest microcontroller around. The FPGA...

Ah, I understand. Maybe but that's not work I really wanna do. No point making a state machine to work with a system without another 68000. I just wanna make one state machine. In choosing the MachXO1200, I've basically solved the FPGA capacity problem I was having before, and it's cheap, so I...

And then if anyone ever does a PowerBook or Portable accelerator, it could have just the microcontroller, no connector for the Snapdragon module. I don't think a design with the SD module could fit into the PB100, for example.

Nah, I'm confident I can get it right in just one or two prototyping iterations. I think it would be hard to fit the whole system on the PB daughtercard too. I've found that there actually is a single cheap FPGA that can do all of the bus operations. Not enough pins for 68020 bus but it will...

*must NOT be implemented with Thumb-2 conditional instructions. To be clear, the purpose of writing the decoder and interpreter in Thumb-2 assembly is to ensure that they can run on a cheap ARMv7-M microcontroller. If the interpreter could be written in A64, then it could be faster, but there is...

Implementing the interpretation algorithm is straightforward enough, I would say. The key is to sensibly decode each instruction, that is to say define good classes of instructions to reimplement as operations against the MC68000 state structure. The decoding scheme has to ensure that there are...

The daughterboard is cute lol. Someone oughta make a card that goes on there. Might be hard because of space constraints though. Here are the pieces of the software: Define structure to store the MC68000 internal state Instruction decoding algorithm (written in T32 assembly, purpose is to...

So the next step is to get Lattice's tools for their FPGAs and implement at least the Control Glue to see how many resources it will require. Now I've implemented lots of little state machines in FPGAs, along with a VGA video generator + wavetable synthesizer, but this state machine...

Does the PB100 have a PDS? I can't find the 68000 on its motherboard. Is the 68000 on a card?

The bus stuff I have right now is applicable to the Portable, but I've encountered a little problem. I'm not 100% sure that the FPGA implementing the Control Glue has enough capacity. The Control Glue must not only implement the M68k bus control, but also implement an asynchronous interface to...

Not exactly, at least I don't plan to do it personally, just trying to make the has the ability to emulate a video card with that functionality. I want the accelerator to have the capability either emulate any peripheral, with the Macintosh running on its own processor at normal speed (i.e...

Hm. 40 MHz is pretty fast. I’ll make sure all 68030 cards are good up to 40 MHz bus clock, in case someone tries to apply an adapter to use it in an IIfx. I’ll also only use signals common to all 68030 machines, so any adapter should work. I really wanna do a multifunction NuBus video card...

That's crazy! I've never heard of doing them in Illustrator. Most of the boards I work on have 50+ components. I think this board will have around 120 :\. So the EDA program is important. KiCAD is actually a pretty crappy program, but it's the best free EDA/CAD program so I've gotta use it for...

Great link. That really explains it. Especially nice to see was the list of all primitive operations accelerated by the 8x24GC. Thanks.

Yeah, Radius's socket thing that sits on the 68000 looks really promising. I wonder why they had to have a second 68000 though. I guess this accelerator must predate some software present in the rom to hand off control to an accelerator. I will have to investigate this further. Here's some...

Title says it all. How do the NuBus cards which advertise QuickDraw acceleration do it? I've read much of Designing Cards and Drivers for the Macintosh Family, but there is no mention of video acceleration in there. Is the acceleration just some blitter functionality, where the card moves memory...

I've just redone the clock system, and fixed a problem with some of the level shifters. The way I was doing the /BG and /BGACK signals would have been way too slow for operation at 8 MHz. Maybe 2 or 5 MHz max. So I fixed it. While doing that, I managed to add the ability for the card to function...