Workshops
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Workshops
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This is the year 3217. These are the adventures of the USS Ent... oops ... sorry, wrong channel ...
This is the year 1987. It is Christmas Day and I am over the moon because I have been presented with an Amiga 500 :) Hooray!
Everything is super, impressive and fast. Fast forward to 1992/93 ... The A500 has sprouted a second floppy, Kickstart 2.05 and its memory has quadrupled to a massive 2 MB. The magazines are full of turbo boards and harddisks and I start to dream...
Now it's the year 2000 ... Wow, what progress! ;) The A500 is retired to a cupboard and on the desk or under it there is a towered A4000 with all extras, beside an A1200 working as a server.
I sit and think about the good old days. What was I up to 5 or 10 years ago? Off I go down to my magazine collection (I can't throw anything away!). There in the dark are the boxes filled with old Amiga magazines (cough, dust). Open the first treasure... 8/92. Hey, I recall this edition like yesterday :). Is it really sooo long ago?
While browsing I find an article marked with red. It is a test report on the "Blizzard Turbo Memory Board", which housed a 14 MHz MC68000 and up to 8 MB memory plus a "Shadow Memory" for loading a kickstart image. Yes, now I remember: that was the next thing I wanted for the A500 in those days. A glance at the price, and I get a shock ;) no way could I have afforded it at that time! ... but maybe now...
Jumped on the A4000 and took a look around the Internet. I plan to awaken my A500 to a new life! I figure I could also fish around for all those good old games and play them once more:). And lo, a Blizzard is for sale, including 3 MB RAM! And the price? Just a fraction of the old days! The 50 DM are transferred quickly and the board is in my hands.
Open up the A500 and ... baaah, wait a minute, what is that? A kickstart selector board is in the way! Hey, I had completely forgotten that! What shall I do? Which ROM should I leave in? Kick 1.2 or Kick 2.05?? Mmmmh ... Kick 1.2 is the best for the old games, for the rest I could use the Shadow Memory! But the Shadow Memory has to be fitted first! What do I need? Aha, 4 ICs making 512 KB altogether. Consulting my Conrad and Buerklin catalogues proves some prices still shock.
But wasn't there something else with 512 KB? Yeah, the old 512 KB memory extension prior to adding the 2 MB board! Where did I put that old board??? After turning my room upside down, the board finally appears. Now I have to tidy up (again!).
Quickly the 4 memory chips are levered out and inserted into the Blizzard. All right, the first test run can begin! Power up! Running! Huzza! :) Quickly load Kick 2.05, which I had read out before, into the Shadow RAM with help of the supplied tool. Kick 2.05 is in and runs marvellously! The speed is amazing! The board makes 1.48 Mips and is faster than the standard A500 by a factor of 2.67. And fortunately it can be switched off.
When surfing the Internet again something else occurs to me. Yes, I need a 1 MB Chip RAM Agnus! Quickly a "72a" is gotten hold of and because the 2 MB extension offers the option to address 512 KB as Chip RAM, the Agnus is installed right away! A jumper is connected from the Gary adapter board to the case and now I'm ready to change from 512 KB to 1024 Chip RAM.
Settle down to play a few games ... :( Ouch, this is no fun with Monkey Island 2, even with 4 floppy drives 11 diskettes are too many!
But wait! Aren't there harddisk controllers for the A500? Again onto the web and search! Soon an internal board is discovered, an M-Tec AT-500. Will it fit into the housing? What does it look like, anyway? Down to the mag archive. Yes, a test report is found right away, but no picture. Only the recommendation of the editors etc. A top device, but no picture! Go on, must be an advertisement somewhere :(. Ah, finally a picture :). The board is small and very thin, will it fit? I dare to order the board, at 37 DM you cannot go wrong (board is used, of course. In the past it was much more expensive!)
The board arrives really fast, but as usual I am extremely busy, so it takes some time until the big tinkering starts ;).
Saturday morning. A perfect day for handicraft :) Get the A500 and open it up! Which is the right way to install the part? On top or below the Blizzard? I first try it on top of the Blizzard, because it looks better. And this unfortunately is a mistake! N ot everything that looks well on first sight really works! My first concern is that the Blizzard's 14 MHz clock is giving the controller problems, but that doesn't seem to happen. Instead the Blizzard's memory has stopped working! Aargh ...! Put that aside for the moment, because there's another snag! With Kick 1.2 neither the 1 MB Chip RAM nor the harddisk works. And the installation of Kick 2.05 is not the answer, since then all the old games will not run. That means, Kick 1.3 is needed.
Off to the Internet where I find a kickstart selector board with ribbon cables! With help of ribbon cables the board ought to be far enough away. Ordered on the spot - 18 DM including Kick 1.3 is a bargain, isn't it! The next weekend is nearing and the A500 readied for tinkering. Selector board in, with Kick 2.05 also on it. With all the dangling cables, not an easy job; could be a problem with the addresses. Ok, installed, the controller goes in first and on top the Blizzard. POWER ON! Nay :(. Oh yeah, the power supply is howling wierdly ... Luckily I still have a spare from the A1200! Connected and off we go!
Guru! Heeyy? Guru? How? What? Where? Why??? Switched to Kick 2.05. Guru again! S***, what causes this? Incompatible, a little voice is saying deep in my mind. No, this must not be! Not now, when I have gone so far! So everything removed and tested part by part. Aha, the IDE controller makes this s***! Now the scales fall from my eyes! The harddisk I'm using (2.5", 170 MB) came out of the A1200, and had SFS file system, 020 version installed. Cannot work! Switch off the harddisk. Aaah, it boots from the diskette! All right, format the harddisk, install OFS and test again. RUNNING!!! Huzza :) This is to our liking! Now I have 14-MHz power, harddisk and 1 MB Chip RAM with everything completely switchable. This way I can play those super-old games again. This I call 100% compatible!
Oh no! The sheet metal shield does not fit any more! Well, then leave it out - but the keyboard won't go in either. This sandwich of boards is too high, but only by a few millimeters! How do I save space? Oh yes, remove the support socket and try again! Still no fit, several capacitors are in the way! But I am a clever guy by now and know which end of a soldering-iron to hold. Remove the caps and solder in flat! S***, does not fit yet, because now the ribbon cable gets in the road! To be correct, it is the plug inserted in the ROM socket. Hey, I don't need that anyhow! ROM socket soldered out, ribbon cable socket soldered in. Now it must fit! Really, the cover closes. Will the metal screen fit as well? I try and it does! As a bonus it keeps the sandwich snugly in place. The harddisk is fastened with doublesided adhesive tape to the shield. Closed and screwed tight and WOW: All is in and running!
Oh, still a miss! Yes, you're right, the LED of the harddisk! Get the drill, make a hole. Glue in the LED and connect it with the IDE controller. No light ...! Of course, wrong way around! All right, but now I'm happy :) It took a few years before I was able to afford all this and the set-up is not totally up-to-date, but it is mine!
New specs: Amiga 500 rev. 5 with "Blizzard Turbo Memory Board" 68000/14 MHz + 3 MB FastRAM + 512 KB Shadow-RAM, M-Tec AT-500 IDE-Controller with a 2.5" 170 MB harddisk, a "Fatter Agnus 72a", switchable between 512 KB and 1024 KB, a kickstart selector board with ribbon cable and fitted with Kick 1.3 and Kick 2.05, a slow-RAM memory extension board, of course disconnectable by switch as well.
Now in fact only an internal flicker-fixer board is missing. and this just might fit inside. But this will be the end! ;) The controller offers well over 1.4 MN/s at the harddisk, which is quite sufficient. With a better cache setting additional kilobytes should be possible. There is only one fly in the ointment: the external "Action Replay MK3" module uses the addresses from 400.0000 and up. The Blizzard's memory uses the address range from 200.0000 to 4ff.ffff so you can imagine what happens if you activate the Action Replay.
Guru-Guru-Guru! But luckily the memory on the Blizzard can be switched off, which lets the module work :)
Happy Hacking! With this machine you easily reach 1000 keys/s with the rc5 client.
I hope you found this little story amusing. If there is someone trying to replicate this who can't work out how to proceed at some stage, please give me a message ;) And if there is anybody out there who does not believe me, I will gladly send a print-out of the SysInfo output =)
Dirk Wenk <dw@teleservice.com>
