PCMCIA A1200 myths

[LaserBack]

hi

I have an A1200 with + TRA1200 turboboard 8mb ram and 020/28mhz
and I have tryed a 56k modem and a lan and both works fine and I can join internet
also I tried a pcmcia/cf flash adapter and worked fine transfering data

so

how this can be possible if I have the card with 8mb ram and professedly the turboboard is pcmcia uncompatible if more of 4mb ram is used?

also I do not need any patch or hack for the reset pcmcia problem that I heard...
all the pcmcia devices works fine after reboot

can anyone explain please? thanks

[LaserBack]

I also have had an TRA1200 board with 8MB RAM and it was also PCMCIA friendly.
It could do everything with the PCMCIA port. However... this was only the case
with the following combination:

Kickstart ROMs 3.0 + WorkBench 3.1 -. PCMCIA WORKING!
Kickstart ROMs 3.1 + WorkBench 3.1 -. PCMCIA NOT WORKING (only with 4MB SIMM).

So I'm curious what ROMs you're using?

I'm using roms 3.0
however if softkick to kick3.1 using skick pcmcia do not works anymore
so I calculate there is some kind of strange issue on kickstart 3.1
also for games it is better and compatible stay  with kick 3.0
some floppy game like GODS do not work with kick 3.1 but works fine with kick 3.0

[LaserBack]

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

[LaserBack]

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

[LaserBack]

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

it seems that if you have kickstart 3.0 on your A1200 the pcmcia slot will works fine with your new turboboard
but if your A1200 have kickstart 3.1 the pcmcia slot will not works if you have 8mb ram...will work only with 4mb

I think is a serious bug in Kicstart 3.1 or commodore did it purposely to avoid conflicts with pcmcia ram cards......anyways was a stupid mistake cause lots of devices works ok

please post your results later when your turboboard arrives

[LaserBack]

I might be wrong but I seem to recall reading in the 3.1 release notes that come with the NDK that they did do it on purpose.
 
It was a stupid mistake because PCMCIA IO cards should be 100% compatible with 8mb of fast ram in the Zorro II space. It's only PCMCIA RAM cards that would ever have a problem & why would you bother with those if you had >4mb of RAM anyway?

I agree with you...
was really stupid..why you will insert a slow pcmcia ram card if you have 8m fast ram......
what kind of dumb will insert that to slowdown the systrem?
anyways we're not talking about pcmcia cf flash adapters or ethernet cards that not existed in 1993
they forgot modems, squirrel scsi,scanners and other devices that would operate very well on the era
and the big problem is that this mistake affects to all A1200 ram-boards,all 020 turboboards and some 030 turboboards....
in other words....affects the vast majority of the A1200 out there

also there is another stupidity.... on KICKSTART 3.1 they modified something related to ready signal...and some floppy games that worked on kick 3.0 not works on kick 3.1.....even with original amiga drives....anyways this can be solved by software using relokick,skick or any other sofkicker


btw, where are those kick 3.1 'release notes?