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Amiga 1200: ACA1220 + PCMCIA Network Cards

This has been a battle. I'd purchased the A1200 and was playing games... but realised I needed more RAM. So I found an Apollo 1220 online and purchased that. Little did I realise this was an actual Apollo.. I had initially (mis)thought that it was an ACA1220. Not wanting to admit defeat, I ran with it anyway. My machine now had 4mb of RAM, instead of 2mb, and I was able to do more things.

From there, it was time to connect to the local network to ease file transferring and also enter the world wide interwebs. This was to be easy; find an appropriate PCMCIA card and configure the software. And it worked fine, I purchased a compatible card and got the Amiga online. Unfortunately, with only 4mb of RAM, I found that I only had around 100kb free once connected... no good.

Hunting for an accelerator... I wrangled a swap of my Apollo 1220 + cash for an actual ACA1220. Hurrah! It arrived.. but then I had to head overseas for 3 weeks... so I've only just gotten back to it.

Installing it, I booted into my KS3.X + OS3.9 WB and attempted to connect to my access point. This was the same CF HD, same configuration, same everything that had got me online before. Unfortunately, this time, whilst running WirelessManager (the tool that comes with Prism2v2) my Amiga 1200 locked up (froze) as soon as it attempted to talk to the real world.

Diagnosis time. The only thing that had changed since I was previously online was the accelerator. The ACA1220 is very much targeted at people that don't want to configure things and comes stock with a very compatible configuration. It even boasts "PCMCIA Compatible." I've got a few more cards on the way also... just to determine if my setup works with non-wireless cards. There a forum post here where the author has successfully used PCMCIA-CF adapters, but not wireless cards.

Further into the internet and I came across this post describing how RESET is called during initialisation and that the author created a home-made reset switch for the PCMCIA socket and managed to baby the card into operation. The computer would still freeze at initialisation but, from what I can tell, he got it up and running. This makes me think that a proper hardware RESET fix is required. There's two mentioned below.

TL;DR: It doesn't work. Don't try and use a PCMCIA network card with an A1200 that has an ACA1220 in it! I have successfully used a PCMCIA-CF Card adapter and transferred files... but any network card I try locks up the system! (Update: The ACA1221 works fine!)

Here's a list of fixes I've applied to try and get this thing working:

Power Supply

I had a hunch that the Amiga was struggling since I'd added the PCMCIA, an Indivision AGA-MK2CR and the ACA1220. There was possibly not enough current available to handle them all. After purchasing and wiring up an new and way-overpowered ATX power supply, I still had the same issues. Either way, here's the article if you want to learn how to wire up a new power supply.

Motherboard Capacitors

Further to inconsistent power supplies, capacitors can cause phantom issues in electronic systems. I've just watched a great video series on the repairing of a Sony-Nintendo Super Nintendo CD Prototype. You'll find the videos here: Part 1 and Part 2. Ben Heck managed to get the CD Drive component working again by replacing faulty capacitors.

This is a known issue with the Amiga 1200 and AmigaKit has everything you'll need to replace them. If you don't want to replace them yourself, then they also provide a capacitor replacement service.

I've ordered the pack for the A1200 and I'll update again once I've done the swap.

Motherboard Timing issues

There's articles everywhere (including my own one here) on this... but the Commodore manufacturing employees seem to have gotten confused on the assembly line and installed some components where they shouldn't be. Ian Stedman has a great article on how to fix this. It doesn't directly mention the ACA1220, but I applied the 'ACA' fixes anyway... to no avail!

Kickstart ROMs

Thinking that my Cloanto 3.X ROMs could be the cause, I tried to swap them out for the original KS3.0. I couldn't boot my main HD, so I used the NetworkBootDisk here. No luck... event the SetPrism2Defaults app locked up the machine when trying to configure the card.

Amiga OS Version

I had OS3.9 on the CF Card and thought any number of supporting libraries might have been causing conflicts... Unfortunately they weren't. Cold boots with the boot disk mentioned above didn't help at all.

IDE to CF Card Adapter

There was a forum post here that mentioned the IDE to CF Card adapter and/or brand of CF card was the issue. I removed my altogether, but the machine still locked up.

CardPatch & CardReset

No combination of either of these, before or after SetPatch, did anything. There's also the resetpcmcia flag on acatune, but that didn't help either. Every now and then the PCMCIA card would stop the Amiga from booting, but this didn't worry me at all... you just need to pop it out and in again quickly to get it to continue.

Hardware PCMCIA Reset Fix

Just to quell a few advisors, I applied this fix as well... it did prevent the reset issue when the machine wouldn't boot... but had no effect on the card initialisation freeze. For those playing at home, connect a 10uf electrolytic capacitor from R715A to pin 5 on the Gayle chip. Further instructions are here.

'Gayle Reset Fix'

There's another reset fix for the IC that controls the PCMCIA Port, of which I soldered the capacitor to in the attempt directly before this. The IC is known as the Gayle chipset and Retro Kit came up with a nifty solution for the issue. Just like the Indivision aga-mk2cr, this fix involves a socket for the IC that slips on backwards. It inverts the reset signal so that PCMCIA cards will function correctly.

Here's the same fix from Amiga World in German. This time we get the component list. I'm going to purchase the components tomorrow and give this a go. If it works, then I'll buy the real thing from AmigaKit.

The parts cost less than AUD$1.00. The installation was very easy... the outcome was: waste of time. The freezing still occurs.

ACA1220 timig issue?

Is there a chance that the speed of the ACA1220 is impacting the function of the PCMCIA chipset? There's an option to overclock the card... a solderable SMD resistor. It's actually a 0hm jumper... so it just needs to be bridged rather than another resister put in its place. I could attempt to over/underclock the accelerator card. This would possibly limit the speed of my machine, but would still give me the RAM. Of course, it'd void my warranty.

I clocked the card from 25mhz to 30mhz and the freeze still occurs. I should probably try slowing it down...

Interrupts

IRQs are a part of every computer. You'll find that most hardware has a direct line to the CPU to indicate that it desperately needs to do something. These are known as Interrupt Requests. They do exactly that; interrupt the CPU and then run the specific code that the programmer has attached to handle the interrupt. If there's no code there, then there's a problem... as the interrupt will therefore lock the CPU. Currently... this seems like the most probable cause. The WIFI card or PCMCIA chipset is causing an interrupt of which is not handled.

Looks like I can redirect debug output... might help with diagnosis. Further information here. Seems to all be for OS4 though.

I'll keep digging and update this as I find out ways to catch these unhandled IRQs.

Give up and use a USB to Ethernet adapter

This is a valid answer... but you'll need to buy a USB card first. I've now purchased a Rapid Road interface to go along with the ACA1221 that I mention next. Once they arrive I'll experiment with USB to Ethernet devices. I just happened across one at Trash and Treasure this morning. Got a 2-button joystick and a Netgear FA120 for AUD$10!

Give up and try the ACA1221

The ACA1221 has half the RAM. It actually comes crippled, and you then purchase licences to unlock features... a very interesting model. I ended up purchasing this model accelerator and the wireless PCMCIA card works fine!

Other Sufferers

Amiga 1200 freezing/crashing issue
Trying to get my a1200 online using my NetGear MA401 WiFi card
WLAN Problem
Вот, купил себе Амигу... :(
PCMCIA nie działa (albo coś koło tego)
A1200 freezes when using PCMCIA Network card