I consider this thread very interesting My Amiga 1200 (will unwrap it this evening) will have a 030 turbocard, also with 8MB RAM. I'll be using a PCMCIA ADF Transfer Kit, so I'am looking forward to face that issue...

However, as I've learned here in the last days, the trick might be that some expansion boards use different methods to address extra RAM and thus, do not intervene as much with the maximum address range.

Awaiting a better explaination from a hardware guru

- Gil

Does the PCMCIA card work when you cold boot? I know it doesn't on any of mine - I need to reinsert it after the machine has booted. This is a known issue with the design of the A1200 motherboard (something to do with the card reset line being inverted or something) and can be overcome with a hardware fix, or worked around with a software fix.

The 8MB thing comes into play when an accelerator does not remap the 8MB of memory out of the Zorro-II window. As the A1200 accelerator bus only carries the first 24 bits of the address bus, the accelerator slot can only support 8MB of RAM. The more basic accelerator boards simply use this bus and so are also limited to 8MB RAM. The problem comes from the PCMCIA slot being mapped at an address 4MB into this 8MB window, so effectively it conflicts with the upper 8MB on the accelerator. So, software trying to write to the PCMCIA card will also be trying to write to the RAM above 4MB, and that's never going to end well, but you might just be lucky enough not to be using the memory at 0x0060 0000 for anything critical, and so your machine doesn't crash. It is really odd though that it works at all - you sure you don't have that accelerator jumpered to 4MB?

More advanced accelerator boards get around this by using their own 32-bit addressing, and so therefore can map the RAM to a nice safe address above the 24-bit limit. This also has the effect of allowing more than 8MB.

Anyway, neither of those issues are myths, they are hard facts which can be seen from the A1200 schematics. It's possible you're just very lucky and your hardware doesn't need the PCMCIA reset signal, and some odd configuration thing lets the accelerator and PCMCIA play nicely...

Does the PCMCIA card work when you cold boot? I know it doesn't on any of mine - I need to reinsert it after the machine has booted. This is a known issue with the design of the A1200 motherboard (something to do with the card reset line being inverted or something) and can be overcome with a hardware fix, or worked around with a software fix.

The 8MB thing comes into play when an accelerator does not remap the 8MB of memory out of the Zorro-II window. As the A1200 accelerator bus only carries the first 24 bits of the address bus, the accelerator slot can only support 8MB of RAM. The more basic accelerator boards simply use this bus and so are also limited to 8MB RAM. The problem comes from the PCMCIA slot being mapped at an address 4MB into this 8MB window, so effectively it conflicts with the upper 8MB on the accelerator. So, software trying to write to the PCMCIA card will also be trying to write to the RAM above 4MB, and that's never going to end well, but you might just be lucky enough not to be using the memory at 0x0060 0000 for anything critical, and so your machine doesn't crash. It is really odd though that it works at all - you sure you don't have that accelerator jumpered to 4MB?

More advanced accelerator boards get around this by using their own 32-bit addressing, and so therefore can map the RAM to a nice safe address above the 24-bit limit. This also has the effect of allowing more than 8MB.

Anyway, neither of those issues are myths, they are hard facts which can be seen from the A1200 schematics. It's possible you're just very lucky and your hardware doesn't need the PCMCIA reset signal, and some odd configuration thing lets the accelerator and PCMCIA play nicely...

I'm using 8mb the board is jumpered to use 8mb ....I can jump it to use 4mb and works also
btw,
I don't know what is cold reboot...if you can explain
I reboot the computer using the amigakeys and the pcmcia cards are still working ...so maybe the reset bug apply to certain pcmcia devices and other pcmcia devices are not affected
all of this is rare

Cold/Hard reboot/reset = turning the power off and back on again.
 
Warm/Soft reboot/reset = using the Amiga Keys to restart the Amiga.
 
As was earlier posted, you can tell if you have the hardware fix already done if:
1) you leave the PCMICA card in the slot
2) do a cold start on the Amiga
3) The card works!
 
If it doesn't work, you don't have the fix.

ok I have tested the 56k modem and the cf flash adapter with a cold reset...both cards works fine...no need to remove and insert again
I haven't tested the lan cause I haven't it right now...but I'm sure will work without any fix or patch

btw, my A1200 is original never was fixed or dismounted from the case....the blind armor is still there and never was removed for anything...I only disarmed the computer to connect the hardisk or to clean the floppy drive

It depends on the card. Some (most?) cards will let your PCMCIA work just fine.

This hits it. I used an A1200 for years with a DKB '030 card, with at least 32Mb of RAM (up to 128Mb), and a Squirrel SCSI or LAn card in the PCMCIA slot. I used 3.1 ROMs with 3.1 or 3.5OS. Everything worked fine.
It all depends on the card, AND where the RAM is mapped. AFAIR the 4Mb problem was only with early cards....

Only PCMCIA RAM cards should cause a conflict as PCMCIA IO cards are mapped to a different area of memory outside the 8mb allocated to fast ram.
 
000000 to 1FFFFF 2 MB Chip RAM(or system ROM overlay)
200000 to 5FFFFF 4 MB Zorro II expansion space
600000 to 9FFFFF 4 MB Credit Card memory if CC present
AOOOOO to A1FFFF 128 KB Credit Card Attributes
A20000 to A3FFFF 128 KB Credit Card I/O
A40000 to A5FFFF 128 KB Credit Card Bits (similar to CDTV)
A60000 to A7FFFF 128 KB PC I/O

As said above, it is possible to have more than 4MB fastram together with PCMCIA cards however it won't be in one continuos adress space, don't know exactly what that limitiation will do, anyone?

Here's an even funnier peice of kit in my collection... it support 9MB and PCMCIA compability: http://amiga.resource.cx/exp/alfaram1200

The need for the PCMCIA reset fix depends on the PCMCIA card. For example, most 3Com ethernet cards don't need the fix in normal circumstances, but the fix may be needed when rebooting after a crash (because the card wasn't shut down).

@Daedalus

Why don't you use the software fix to avoid wear and tear on your PCMCIA slot? :-)