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4MB RAM for the IIgs

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I bought my first NEW hardware for any of my Apple II series computers: a 4 MB RAM card for the Apple IIgs!
This tiny card, compared to my old 1.5 MB AE GS-RAM, is made by an American company called "Garret's Workshop" and is sold for only $35! This is nearly half of what the cards of competitors cost.

I haven't had much time to do testing, but it worked right out of the box, although I did not expect anything else from a RAM card ;-)

I was told by the guys from Garret's Workshop that they are up for some more cards, soon.



Prototypes for the new AppleIISd hardware V1.2

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A couple of days ago, the prototypes for the new hardware version 1.2 of the AppleIISd arrived. As you may tell, I made a few changes from the original design: the CPLD and the EEPROM are now SMD components, the programming connector for the CPLD is a component-less Tag-Connect, the 3.3V converter was changed and the pullup resistors are now an array. I am quite happy with the design, but I will have to change a few things for the final version, but that is what prototypes are for!

The pin header for CPLD programming will be reintroduced but not equipped next to the Tag-Connect, necessary adapters are not really cheap. The slot connector will have longer pads. The third thing I still have to figure out is the following: about every tenth time the machine is switched on, the first byte of the EEPROM gets erased and I still have not quite figured out why. I am not sure if this happens on power-up or power-down. Adding pullups on the /OE and /WE lines helped to reduce the error to about…

Glorious Technicolor, again

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Last year, my Commodore 1084S monitor that I used with the IIgs failed with a high pitched whine. Research showed that this seems a pretty common failure where the flyback transformer and or the HOT (horizontal output transistor) kicks the bucket, probably due to bad capacitors in the power supply. Oh, and the power switch failed, too, so that it was permanently on. Another common failure.
I looked on eBay and learned that these monitors fetch prices of 60€ and up, excluding shipping. I paid about 15 Eur for the monitor when I bought it 16 years ago when nobody cared about all that retro stuff. I happen to know the exact date: it was my 18th birthday when I went to a local collector and bought, besides the monitor, a Commodore CBM 8032 computer, a CBM 8050 dual floppy and a CBM 8024 printer (this thing is a huge 15" 9-pin printer!) for 50€. Nowadays, the components fetch 200-300€ each! This purchase, aside from a C64 I was given previously, started my retro-computing career. I bo…

Firmware flasher for the AppleIISd

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The last year has been surreal. With 80 shows of 'The Hunchback of Notre Dame' 🎵 and four other projects I very well may say that I have never sung so much in my life. Now that the run of the musical is over, I have had a little more time to return to retro computing.
A little while ago a guy from the Applefritter forum contacted me and asked if I were interested in making another batch of the AppleIISD. I said yes but I wanted to make some changes, first.
One thing I thought of right from the start was the ability to update the card's firmware within the computer and without having to remove the EPROM, erase it and burn it. At first, I thought of using a battery-backed SRAM chip, but that did not work for some reason and the two I had had dead batteries despite having been sold as 'new'. However, for development, I was using an EEPROM anyway, so I decided on using one instead. I don't know why I did not have the idea before. Maybe, I was under the impression…

Version V1.2 for the AppleIISd released

It took a little longer than expected, but I have just released the version 1.2 for the AppleIISd!

As mentioned in my last post I had the nasty issue that booting GS/OS crashed when AppleShare was loaded. I have not found out completely why, but I seem to have solved the problem.  I posted my problem over at the comp.sys.apple2.programmer group and drew the interest of Apple IIgs legend Antoine Vignau. He was kind enough to go through my code, told me a few tricks and found the bug, eventually.

The image is available for download on my repository: GitHub

The AppleIISd gets smart

It seems impossible that almost exactly six month have passed since my last blog entry and contribution to my AppleIISd project!
On the start of the new year I joined the choir of a professional production of Disney's The Hunchback of Notre Dame and was busy rehearsing all of January and February. Since then I have had a show at least twice a week. 🎵 In March and April I was busy moving flats and had been unpacking and rearranging stuff. I have only had time to get back to the Apple II in the last couple of weekends. However, I tried up a Smartport driver implementation for the AppleIISd using the very little information that is available: 
The name Smartport stands for both hardware and software. The hardware part is what most Apple II users are familiar with: it manifests itself as the disk port on the IIc, IIc+ and the IIgs. It is capable of talking to dumb 5.25" drives as the UniDisk and the DuoDisk, as well as both intelligent and unintelligent 3.5" drives. Theore…

How to prepare SD cards for the AppleIISd

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Here is how to prepare SD cards for use with my AppleIISd. Please be aware, that the AppleIISd does not use the FAT format like other SD or CF storage solutions does, it uses the ProDOS format directly. This means that you can not simply take a ProDOS image and drop it to the card in the Windows Explorer, it has to be written using CiderPress.

1. Open CiderPress in Admin mode (Right-click on Icon, "Open as Administrator").
2. Select "Volume copier" from the icon bar or select "Tools -> Volume copier (open volume)" from the menu.
3. Make sure that "Open as read-only" is deselected. Select the SD card's logical volume from the list. Triple check that you have selected the correct volume and don't come crying when your PC has only a ProDOS volume left to boot 😉


4. When you open an SD card for the first time like this it might show an MS-DOS volume with SD card's size. This gives you an opportunity to check again! Select the volume a…