cdtv rom's

[karsten]

So what is the correct eprom that the cdtv can use?

As said before 27c1001 work fine if you swap the two pins (but 2<>24 not 22)

I found that the new roms are a lot bigger than the old ones. The old ones are 32KB?

Where did you find that? AFAIK all CDTV extended ROMs are 2x128KB

The version number jumps up quite a lot to version 2.3 what are the main differences?

First one thing. It's version 2.30 and not 2.3 (not the same as it's not a number, but a version number; 2=major version, 30=minor version). Also the version numbers in ascending order are as follows as can be found out by checking the dates (listed are the versions where I know an image can be found somewhere):
ß2.9 (it is not the latest as written at cdtv.org.uk, it's a beta version)
0.1 (gamma version)
1.0 (the one from the original CDTVs)
2.7 (don't know where that comes from, does anyone know?)
2.30 (from A570)

cdtv.org.uk also states there's a 3.2 for the CDTV-CR, but I haven't seen it yet and don't know if that would work in a CDTV

Can 2.3 use 2.04 or 3.0 kickstart roms?

2.30 works with higher Kickstarts as 2.7 does too

What about 2.9 are there any bin files for those?

In the 2.9 archive at cdtv.org.uk (file ROMCode). You would need to unpack the dms and extract the file and split it in even/odd, but as I said, this version is actually the oldest (it's ß2.9)

to bad the waw scsi interface is so hard to find. Has anyone one for sale?

Actually, you can buy a licenced version of the W.A.W. SCSI controller at http://www.cnctechniker.de/ (click on Amiga, ordering from mid-September again as he's busy currently). Don't know if he speaks English, also the manual is in German too (it's the W.A.W. manual), but it's not really needed. Price is 70 Euro+shipping

[karsten]

The cdtv uses 28 pin roms so I thought it must be 32 KB roms.

No, it uses 32 pin roms.

[karsten]

Not sure which ones are unused, looking at the schematics, I couldn't find 4 unused (and each rom is 128KB and it clearly has 17 adress lines)

[karsten]

That would be pin 1 (Vpp), pin 2 (OE), pin 31 (PGM), pin 32 (Vcc). I doubt they would work if all 4 pins are unused and still there would be 17 address lines connected to the address bus

[karsten]

Never seen ROMs with those pins missing, do they work that way, i.e. do you get the CDTV boot screen or a Kickstart boot screen? I would think you would need at least Vcc for the ROMs to operate. Still doesn't explain how do you get to the 32 KB, as there are no address lines missing.

[karsten]

Looking at BBOAH, there indeed seem to be 28 pin ROMs. But those are no EPROMs as there is no quartz window for erasing. It could be that this is an OTP ROM, which I doubt as it would have not enough pins for programming, I think it's a ROM chip and Vcc connects also to pin 28 of the ROM (would be pin 30 of the EPROM, no internal connection on a 27c1000). In my CDTV there was originally a 27C1000 EPROM with 32 pins, so they used both.

[karsten]

the question remains can i stil use eproms if I switch the 2 pin's ?

I see no problems I have something similiar to a 27c1001 and Rev 2.2.1 and it works fine

32KB, A friend of my lookt in his eprom database and the bigest one he could find with 28 pin's was a 32KB prom Any bigger it would have 32 pins. But it seems we where wrong ;-)

You are not wrong, with PROMs you can have 32KB, but this 28 pin ones are no PROMs, those are unprogrammable ROMs, therefore less pins are needed.