Incidentally, in your code, I noted you defined your PINNODE s using distinct numbers. In most cases, you should let the fitter make PINNODE assignments. I have E-mail somewhere from Atmel technical support making that recommendation and explaining why, but can’t seem to locate it.

I read ...

Thanks, BDD. That’s odd, though. I have to say, the behavior of WinCUPL under Win11 on my PC is erratic at best.

Jonathan

I think I will put this effort on hold until I get back to my lair as it's too painful without a scope. I need to at least see if the Gowin documentation about phase adjustment vs. duty cycle is correct, as the examples in the wild (e.g. NESTang SDRAM controller etc) don't quite match up.

In the ...

I guess I have good timing - this thread is alive! I've been trying to use Quartus II to demux a 65C816 (data and bank) using an ATF1504as 7.5ns, but to no avail. I switched to WinCUPL, but I feel like I'm banging my head against the wall. I'm sure people have done this before; but I just can't get ...

Sure would be fun to play with one.

Ditto - I've only used HDL until now, too. This is very different.

Jonathan

I'm also starting out with an ATF1508AS, so I'll probably have something to contribute here eventually. I'm aiming to program in SystemVerilog exclusively without paying for the commercial packages, but I'll have to see how I go with that over the next few days.

Awesome! Let's keep this thread ...

Just to add another data point - my Ruby '816 board is 130x100mm, double sided and runs very well at 16Mhz (no wait states). It ran just as well on stripboard with dozens of flying wires before I made up a PCB for it.

-Gordon

Gordon,

what are the specs for the RAM and ROM you used (in your ...

My POC V1.2 unit runs at 20 MHz with one wait-state on ROM and I/O accesses.

Yes! This is exactly the kind of "advanced" method I would love to learn to utilize. I've built, either on breadboards, stripboards, or those few ungainly PCBs, some really basic systems with basic IO.

In computer ...

I just sent out 4 designs to JLCPCB, all 100mmx100mm, 20 4-layer boards, 5 2-layer. DHL shipping, $60 total. They all have CPLD which is critical in reducing board size, so are SMT package. Also pack your board as tight as the auto router will handle, and combine multiple designs in one order. This ...

one option: you could try to be lazy like me, in your CAD program put all the ICs on the board with around 200-300mils of space between them, make sure the ratsnest isn't too bad, and then let an autorouter like freerouting do the rest.
and if you're wondering about the quality of the routing job ...

However - also consider what you're getting - could I have envisaged 5 PCBs for that price even 20 year ago? No way. And that's the issue - things like the Raspberry Pi being almost too cheap have forced everyone into a race to the bottom of the barrel.

-Gordon

That is a very fair point.

What ...

This guy, here

ATF1502 is pin-compatible with ATF1504, in fact it is also pin compatible with EPM7032S and EPM7064S. Doing address decodes and data latches, you won't have problem with smaller ATF1502, but if you decided to have more complex functions like internal ROM, serial port, I2C, etc, then you can always ...

The ATF1502AS-7JX44 is a 32-macrocell version of the ATF1504AS-7JX44. Even with only 32 MCs, the 1502 is much more capable than a GAL. That said, I still recommend you do your first build with a GAL to get your feet wet—unless you are going to build your unit with extended RAM, in which case using ...