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VIC-II FPGA prototype


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This is pretty great. 

At this point, all of the C64 components have an FPGA version (and there are obviously full system FPGA cores, at least 3 that I know of.) At this point, someone could build a brand new Commodore 64 using FPGAs to replace all of the custom chips...

 

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Randy is amazing! Both the VIC-II Kawari and the BMC64 are wonderful retro projects. And you can see he knows exactly what he’s doing.

You can replace the SID, the PLA, the ROMs and now the VIC-II.

The CPU you can kind of replace with a 65C02. Are there replacements for the 6526 CIAs, though?

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18 minutes ago, Kalvan said:

It seems to be tripped up by the limits of a stock 6510.

I wonder what would happen if the 64K version was stuck into a Commodore 128...

The 128 would be confused because the VIC IIe has more pins to support extra functionality that they added to the VIC II for the 128. Off the top of my head I think the VIC IIe was a 48 pin package vs the 40 pins of the original. {checks} https://en.wikipedia.org/wiki/MOS_Technology_VIC-II#The_VIC-IIe

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21 hours ago, Scott Robison said:

The 128 would be confused because the VIC IIe has more pins to support extra functionality that they added to the VIC II for the 128. Off the top of my head I think the VIC IIe was a 48 pin package vs the 40 pins of the original. {checks} https://en.wikipedia.org/wiki/MOS_Technology_VIC-II#The_VIC-IIe

The 128 would probably not even boot. The VIC-II is actually responsible for the system clock, and on the 128 that means the 8502 and the Z80 clocks. Aside from that, the 128’s VIC chip has a 2MHz mode and also handles part of the keyboard scan, there are several things that simply would not work, aside from the fact that you’d be stuck at 1MHz.

 

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3 hours ago, TomXP411 said:

The 128 would probably not even boot. The VIC-II is actually responsible for the system clock, and on the 128 that means the 8502 and the Z80 clocks. Aside from that, the 128’s VIC chip has a 2MHz mode and also handles part of the keyboard scan, there are several things that simply would not work, aside from the fact that you’d be stuck at 1MHz.

 

It would definitely not boot. "Would be confused" was my understated way of saying "the signals necessary would not be present because 8 pins minimum would not be connected properly, and probably more because I've not bothered comparing the position of the other pins on the two chips." 🙂

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Okay, I guess that would be a bust unless the creator stuck it on a new riser domino that had room for the extra eight pins.  Message sent and received.

Hmm...

The Atari 8-bit community has various upgrades available to its machines, but they are strictly system RAM upgrades, 65816 processor upgrades, and, with the "Veronica," HDMI/DisplayPort interface for modern discrete pixel monitors.

Why not, in the spirit of this upgrade, FPGA updates to ANTIC and C/GTIA that add a bigger master palette, more colors onscreen, and especially more hardware players and missiles?

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On 9/27/2021 at 9:37 PM, EMwhite said:

So is it acceptable to the no-FPGA crowd to have one or more, or a complete set of FPGA replacements in an original Breadboard?

Maybe it’s the opaque, too much on one chip angle that is the problem?

There are probably as many opinions on it as there are people. Okay, maybe not that much. I'm very pro-FPGA ... I think it's a freaking miracle that we can replicate old chips that aren't cost effective to produce, and I have no problem with a complete computer made out of them myself.

I think some people want an old computer like they want an old car. All original equipment that's been treated well. Of course, you can take "original equipment" and repair it when it breaks. It's a lot harder (aka impossible) to open up a CPU that's had too much current applied and melted the internal electronics and replace a few or more bad transistors or whatever.

I think others are more willing to settle for a dedicated purpose FPGA that fits into a socket on a board and replaces just the one bit of functionality.

Then there are reasonable people like me who don't care. 🙂 

But seriously, I wonder why it is that in 2021 there are people who look down their noses at FPGA to such an extent that they won't even consider using one under any circumstances, yet those people were just fine with magical video and sound chips that offloaded functionality that had previously been provided by the CPU in many systems. At any point in time you can go back a little bit and see that every breakthrough did things in a way that hadn't been done before. Why is a circuit etched in silicon so much better than an equivalent to identical circuit embedded in an FPGA?

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On 9/28/2021 at 1:24 AM, Scott Robison said:

 ... I think it's a freaking miracle that we can replicate old chips that aren't cost effective to produce, and I have no problem with a complete computer made out of them myself. ...

Not sure if it will be broadcast live (if not, probably post event) but Stefany is giving a ‘class’ on how to create a rudimentary video controller on FPGA at VCF East on Friday Oct. 8th.

As you may be aware, she owns C256 Foenix and her VICKY II and III components are built on Altera Cyclone 10 (and now IV) FPGA.

I expect the class/talk to start with the basics (problem statement) of needing to take text or image in memory and manipulate clocking and data sync to fit the SVGA spec as Ben Eater’s Worlds Worst Video card did, but instead, leverage rocket fuel to take this to the next level.

VICKY has all of the bells and whistles (sprites, tiles, scrolling, dual head output and more) but this talk will probably just cover basics.  Should be interesting.

Between some maniac (Ben) throwing graphics from ROM to screen without a CPU to the MiniPet, which uses an Atmel to emulate the CBM PET video circuitry, to SIDs and VICKY / VERA, it’s an amazing thing we are witnessing.

About 15 years ago, the company I worked for bought FPGA tech to process and route virtualized namespace storage network packets at [then] line rates and it was expensive as hell.  Today, you can buy an FPGA Dev board on Amazon for about $150 or less and produce your own!

 

 

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On 9/28/2021 at 8:46 AM, EMwhite said:

Not sure if it will be broadcast live (if not, probably post event) but Stefany is giving a ‘class’ on how to create a rudimentary video controller on FPGA at VCF East on Friday Oct. 8th.

As you may be aware, she owns C256 Foenix and her VICKY II and III components are built on Altera Cyclone 10 (and now IV) FPGA.

I expect the class/talk to start with the basics (problem statement) of needing to take text or image in memory and manipulate clocking and data sync to fit the SVGA spec as Ben Eater’s Worlds Worst Video card did, but instead, leverage rocket fuel to take this to the next level.

VICKY has all of the bells and whistles (sprites, tiles, scrolling, dual head output and more) but this talk will probably just cover basics.  Should be interesting.

Between some maniac (Ben) throwing graphics from ROM to screen without a CPU to the MiniPet, which uses an Atmel to emulate the CBM PET video circuitry, to SIDs and VICKY / VERA, it’s an amazing thing we are witnessing.

 

 

There's no way I can attend.  Could you or anyone else please point me (and the rest of us forum members who aren't on the Commander X16 dev team) to YouTube channels that have committed to filming and posting it after the event?

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On 9/28/2021 at 4:37 AM, EMwhite said:

So is it acceptable to the no-FPGA crowd to have one or more, or a complete set of FPGA replacements in an original Breadboard?

Maybe it’s the opaque, too much on one chip angle that is the problem?

 

It's reality. SID, PLA, VIC they don't make any more. There are still plenty out there, but they are diminishing and you don't want to pull them from other live C64s ; or if you do, you could have one "authentic" C64 and one with FPGA type chips. I think eventually it may become the case for all parts in a C64 that aren't standard 74 series logic. Stocks of 64k DRAMs won't last forever.

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