Would you like to have CRTC 5 in your CPC? About HD6345

[McArti0]

Hitachi HD6345 CRTC-II same pinout like 6845 but 40 registers and 4 split bands.

https://pdf1.alldatasheet.com/datasheet-pdf/view/87406/HITACHI/HD6345P.html

[lmimmfn]

What's the benefit?

[McArti0]

Split screen up to 4 part and other.

[roudoudou]

Hitachi HD6345 CRTC-II same pinout like 6845 but 40 registers and 4 split bands.

https://pdf1.alldatasheet.com/datasheet-pdf/view/87406/HITACHI/HD6345P.html

Toto already mounted one in the CPC-ITX and we played a little with it a few years ago...

This is the OneScreen Colonies (with a bypass for CRTC test) on it

[HAL6128]

Is it easy to integrate it (also from operating software side)?

[McArti0]

Insert to socket. Fully compatible. But it has many extras that Plus doesn't have.

[andycadley]

Insert to socket. Fully compatible. But it has many extras that Plus doesn't have.

If people had been upgrading to it prior to the Plus, it might've been interesting. As it stands what it can do is rather more limited than the Plus in most cases and thus less interesting overall.

If there had been an option for a vertical split, it might have been a more interesting proposition overall, as that's something which is pretty much impossible to do in a performant way.

[roudoudou]

this CRTC is more a super CRTC-2 than a super CRTC-0/1 ...

with basic programms, it will fit

[McArti0]

Its real super CRTC 0+1. R12/13 is RW. R8 is full skev

[eto]

Is the HD6345 available in quantities? If yes, what is its price?

[McArti0]

https://www.amazon.com/1pcs-lot-HD63B45P-HD63B45-DIP-40/dp/B08243ZPCQ

https://mixtronica.com/c-integrados-semicondutores/30244-hd63b45p-crt-ii-crt-controller-dip40.html

~12$ 12€

https://www.digikey.ie/en/products/detail/rochester-electronics-llc/HD6345P/12100478

In-Stock: 197

[th]Unit Price with VAT:[/th] €31.51260

[GUNHED]

Interesting idea!!!

Are there any (worth to be mentioned) disadvantages of the new CRTC?

EDIT: Seems to be very compatible (?), now... seriously... Amstrad should have use it!
Interestingly nobody ever offered it as upgrade or so. 

[lmimmfn]

If its backwards compatible with additional features I'd love to see it in a new CPC motherboard.

I do like speccy next buy chips backwards compatible with additional features I am all for.

[McArti0]

Are there any (worth to be mentioned) disadvantages of the new CRTC?

In the DigiKey store We need to buy 11 pieces at a time. 
I have already ordered a 6128 PCB replica.

[roudoudou]

If its backwards compatible with additional features I'd love to see it in a new CPC motherboard.

I do like speccy next buy chips backwards compatible with additional features I am all for.

as you can see above, its compatible with simple programms, not advanced coding (i remember we tried with different snapshots (for 0 and 1)

[McArti0]

See from page 54 manual. R32,33 Memory width setting. Something like a part window of a larger virtual desktop.

[andycadley]

See from page 54 manual. R32,33 Memory width setting. Something like a part window of a larger virtual desktop.

That probably won't really work in a very usable way in the CPC though, since it doesn't use MA0 - MA13 in the way that was really intended (character based addressing)

[McArti0]

That probably won't...

That's why I joined the queue for 6128 PCB replica. I don't want to solder on my antique. What I have in mind is a printed model for assembly, the CPC6128 case.

[andycadley]

That probably won't...

That's why I joined the queue for 6128 PCB replica. I don't want to solder on my antique. What I have in mind is a printed model for assembly, the CPC6128 case.

I don't mean physically won't work, I mean the actual functionality won't work with the way the Amstrad hardware has to decode addresses. It doesn't really use the CRTC MA and RA signals the way they're intended and the way it does use them won't work with the way the "wider window" approach works.

[McArti0]

The raster is preserved there. This will be the most expensive part of the (non)CPC fun.

[eto]

EDIT: Seems to be very compatible (?), now... seriously... Amstrad should have use it!
Interestingly nobody ever offered it as upgrade or so. 

Indeed, that would have been nice, if they would have included it from the beginning. Probably it was

• too expensive
• or too risky (as no other provider than Hitachi)
• or not available in the right quantities

Maybe even all of it...


Regarding the upgrade: were there any (successful) upgrades that required desoldering a big IC in the CPC? that's usually quite a risky procedure that not many will do.


Btw: I could not find any reference where that IC was actually used. I see it's included in the MAME sources so probably in some arcade machines. But other than that, it's hard to find any information.

[GUNHED]

Yes, Arcade machines used it. 

[McArti0]

https://www.vgamuseum.info/index.php/cpu/item/171-hitachi-hd6445-crtc-ii

[GUNHED]

Just for information: The difference between 6345 and 6445 is the used bus system only, according the the manual.