Ersatz für 8501, 6510T, 6523T etc.

Interesting

We had already finished 6523T and Paddle-PLA, too.

We also wanted to do 6510T, but there are so many other things to do right now. Maybe all in one "double CPLD".

DSCF5554.JPG

My goal was similar to that, but now the CMD things have priority for now. Maybe I'll continue working on it afterwards, I wanted to summarize it further in any case. Maybe androSID builds the whole 1551 into an FPGA

Zitat von MCes

is there any free software available for developing LATTICE CPLD?

Lattice software was freely available - unfortunately since this year no more

But I have access to these tools at my work. Likewise to the Mentor tools for the ATF150x.

Zitat von MCes

o my solution is a 6502A as a CPU and 2x 6522A as 4 I/O port... why not?

One reason would be:

You would have to patch the 1551-ROM to use the 2 x 6522 since they differ significantly from a single 6523.

Thus a 6523 CPLD-replacement would make more sense.

Zitat von toms01

We also wanted to do 6510T, but there are so many other things to do right now. Maybe all in one "double CPLD".

6510T was one of the first things I did.

Zitat von kinzi

Thus a 6523 CPLD-replacement make more sense.

hehe, we already had that one ready, but I messed up with the fitter and have to redo the layout again

Zitat von androSID

6510T was one of the first things I did.

i know, but was still thinking of a 6502@6510T adapter with a 6523@CPLD in one.

Zitat von toms01

i know, but was still thinking of a 6502@6510T adapter with a 6523@CPLD in one.

Ah... I see... we can do that one if you want; the 6510T is easy

Zitat von kinzi

Thus a 6523 CPLD-replacement make more sense.

Patience...

Edge level exact replication is in the works...

PS: 6525 is a superset of 6523

Zitat von MCes

Sorry, but my 6510T+6523A replacement board doesn't need any kernel mods......

Then it is not this:

Zitat von MCes

so my solution is a 6502A as a CPU and 2x 6522A as 4 I/O port... why not?

I think we can do it smaller and cheaper. A 6502 and a CPLD should be enough.

Zitat von MCes

use 2x 44 pin CPLDs

something like this?

Ersatz für 6523 bzw. 1551-Paddle

nem ertem...

MCes

OK, so the GAL does some magic in convertimg register addresses of the VIAs to the register-set of the 6523?

Because that was that what I wanted to say: The 6523 address space differs from 2 x 6522 address space. It also has some specialities I cant recall exactly ATM (different interrupt modes IIRC etc.) which would not be possible to imitate by VIAs, but maybe there features aren't used in the 1551.