Comment by acomjean | Hacker News Reader

Comment by acomjean | Hacker News Reader

When I was younger I too was trading games. Being in middle school my ability to crack games was not great.. It really interesting how clever people get trying to prevent copies and how those counter measures get discovered.

A friend's father got this card that went in the apple // card slot and had a button. If you pressed the button you could dump whatever was in memory at that time to a copyable disk. It was called the "Wild card". This was fascinating to me.. It took some digging but there are a few ads for it on the internet..

I wonder if some of the lack of title sequences and extras were because people were using these cards, adding a "cracked splash" screen and calling it a day.

Ad: "Avoid the IRS (Iandvertently Ruined Software)" https://mirrors.apple2.org.za/Apple%20II%20Documentation%20P...

Ad2:

"Wildcards are copy cards that stack the deck in your favor, rather than copying protected disks track by track like the old nibble copiers, Wildcards ignore the disk and any copy protection on it. Instrad wildcards take a snapsot of your Apple's memory. This creates an accurate copy of the original program"

https://mirrors.apple2.org.za/Apple%20II%20Documentation%20P...

I built a memory dump system of my own for the TRS-80. The reset button on the machine launched an RST operation on the Z80 CPU, which was the only non-maskable interrupt (in other words, software writers couldn't disable or prevent it).

Unfortunately due to the memory mapping of the TRS-80, this set the CPU to an address in ROM, meaning I couldn't get at it to do anything useful. I put together a small veroboard circuit with a 2716 EPROM and a nand gate or two. This was hacked into the memory decoding circuit on the TRS-80 so that in normal operation the original ROM would be called, but if the address range was in the first 2k (the smallest block I could map), it would take instructions from the EPROM.

A friend then hand copied the entire first 2k of memory from the ROM (in hex) and cooked it into the EPROM (funnily enough using an Apple). However, we modified the code around the RST instruction to leap to RAM, where the memory dump program could reside and then be executed.

As the machine couldn't reboot properly until our dump software was loaded, we added a toggle switch to enable/disable the memory mapping hack and return the machine to normal.

Presumably like the "Wild Card" did it, we dumped the memory and register contents so they could reloaded later. Fun times.

These types of freezers were on lots of systems. Everyone in the C64 scene will remember the ISEPIC, for example, which functioned in a like manner (I have an ISEPIC, but I used a Super Snapshot and/or a Final Cartridge III more often -- more reliable and loaded snapshots faster).

Even back in the day these were recognized as lower-quality cracks, but sometimes the best you could do until the protection scheme was better understood.

(ObDisclaimer: not an endorsement of piracy.)

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